Experience You Can Put a Name To.

As CEO and Co-Founder of Centerline Medical Billing, Patrick Mahoney brings nearly two decades of behavioral healthcare finance and revenue cycle management experience, with deep expertise in payer reimbursement, financial strategy, and the economics of operating behavioral healthcare organizations.

He began his career in healthcare finance in 2008 and went on to serve as CFO of a 150-bed, multi-facility behavioral healthcare organization headquartered in Orange County, California.

Patrick’s experience navigating claims across virtually every major insurance carrier has given him a comprehensive understanding of the national payer landscape and how reimbursement, payer requirements, and cash flow impact the financial health of behavioral healthcare organizations. Having sat in the CFO’s chair, he understands these challenges from the provider’s perspective and approaches revenue cycle management with financial discipline and a focus on long-term relationships. For Patrick, one of the most rewarding parts of his work is seeing Centerline’s partners become financially stronger and turn that stability into opportunities for growth.

That same commitment to long-term relationships is reflected in the Centerline team. Patrick worked alongside longtime partner and Co-Founder Gabe Hynes before founding Centerline together in 2018, and several team members have worked with Patrick across multiple organizations.

After 15 years in Orange County, Patrick returned to his hometown of Burlington, Vermont, with his wife and two daughters. Growing up with five sisters, family has always been an important part of his life. Outside of work, he enjoys live music, playing guitar, snowboarding at Stowe, coaching his daughter’s soccer team, and spending time with his family on Lake Champlain.

Gabe Hynes is the COO and Co-Founder of Centerline Medical Billing, bringing nearly three decades of behavioral healthcare experience spanning facility development, operations, clinical programming, and utilization management.

He began his career in behavioral healthcare in 1998 in Orange County, California, and went on to oversee the development and launch of behavioral healthcare programs in Florida and Los Angeles.

In 2002, Gabe shifted his focus to working directly with individuals and families as a Certified Interventionist, completing more than 300 interventions and helping families get their loved ones into treatment. He later returned to organizational leadership, where he continued developing and operating behavioral healthcare programs.

Gabe eventually joined a behavioral healthcare organization in Orange County, where he worked alongside his longtime partner and Centerline Co-Founder, Patrick Mahoney. As the organization grew from 50 to 150 beds, Gabe developed and oversaw the utilization management systems that supported its expansion. That experience helped shape the foundation for Centerline, which he co-founded in 2018.

Today, Gabe draws on the breadth of his experience to help lead Centerline and navigate complex cases and payer challenges. Relationship-driven by nature, he maintains close relationships with clients that often extend well beyond business.

Outside of work, Gabe enjoys traveling with his wife, skiing, and running long-distance team races, trail races, and marathons. A Denver native, he is a devoted Broncos and Nuggets fan and enjoys spending time with his dog, Inca.

Brian Caulfield serves as Chief Marketing Officer at Centerline, with a background in behavioral healthcare that spans both provider operations and revenue cycle management.

After transitioning into behavioral healthcare in 2017, he led admissions for a 100+ bed, multi-facility organization, developing expertise in insurance eligibility, utilization management, reimbursement, and the operational challenges providers face. Before joining Centerline in 2024, Brian worked with the company as a client, gaining firsthand appreciation for its integrity, expertise, and consultative approach.

As Chief Marketing Officer, Brian drives Centerline’s growth through new client acquisition and relationships across the behavioral healthcare industry. He works closely with leadership teams to understand their unique challenges, improve financial performance, strengthen operations, and support sustainable growth. For Brian, the most rewarding part of his role is building meaningful relationships and watching Centerline’s partners succeed.

Outside of work, Brian enjoys spending time with family and friends, exploring new places, surfing, scuba diving, and practicing yoga. He has a passion for adventure and values experiences that offer a different perspective on the world.

With more than a decade dedicated to behavioral health insurance billing, Ariel Sieger leads Centerline’s billing operations as Billing Director, with deep expertise in mental health and substance use treatment reimbursement.

As Centerline's first employee, Ariel has played a pivotal role in the company's growth, helping build the billing department and the revenue cycle processes that support behavioral healthcare providers across the country.

As Billing Director, Ariel leads and manages Centerline's billing team, providing the guidance and oversight needed to ensure accuracy and consistency throughout the billing process. Under her leadership, the team manages claims submission and correction, payer follow-up, appeals, collections, and reimbursement management. Ariel's extensive knowledge of behavioral health reimbursement allows her to support her team in navigating complex payer requirements and resolving challenging claim issues. Known for her attention to detail, leadership, and deep understanding of insurance billing, Ariel has been an integral part of Centerline's success since the company's founding.

Outside of work, Ariel enjoys traveling and is an avid baseball fan. She and her dad share a lifelong goal of visiting every Major League Baseball stadium together, with Oracle Park, home of the San Francisco Giants, as her favorite for its bay views and garlic fries.

Jonathan Estupinan leads Centerline’s Utilization Management team, drawing on more than a decade of experience navigating behavioral health authorizations, payer requirements, and clinical review.

Throughout his career, he has led utilization review departments, managed high-volume caseloads, and developed strong working relationships with facility clinicians and insurance medical directors. His payer expertise and collaborative approach have made him a trusted advocate for providers and patients.

Jonathan works closely with clinical teams to strengthen documentation that supports medical necessity and continued treatment. He is highly experienced in peer-to-peer reviews and has built a consistent track record of overturning denials and securing continued authorizations, helping providers achieve clinically appropriate lengths of stay for their patients.

Since joining Centerline in 2018, Jonathan has played a key role in the growth of the company's utilization management services. His background in utilization management and behavioral healthcare operations gives him a well-rounded understanding of the clinical, operational, and reimbursement challenges providers face.

Outside of work, Jonathan enjoys camping, spending time outdoors, and making memories with his wife and four children. Raised in South Orange County, he values every opportunity to spend quality time with his family.

Katrina DeBiase has built her career in behavioral health utilization management and today serves as Centerline’s Utilization Review Lead, helping providers navigate complex authorization and payer challenges.

She began her career at a large, multi-facility behavioral healthcare organization in 2016 and quickly advanced into utilization review. There, she developed extensive experience managing Kaiser authorizations, commercial insurance plans, and complex clinical reviews while helping train team members and establish new authorization workflows, including those for the Department of Veterans Affairs (VA).

Since joining Centerline in 2020, Katrina has become a key member of the utilization management team, managing Kaiser authorizations across Southern and Northern California, Colorado, and Hawaii, while also overseeing PTSD workers’ compensation authorizations for first responders. She specializes in advocating for clinically appropriate lengths of stay and using her deep payer expertise to secure continued authorizations in even the most complex cases.

Outside of work, Katrina enjoys traveling, exploring historic places, and uncovering one-of-a-kind antiques at estate sales and antique shops. She is also an avid reader and appreciates any opportunity to learn something new or discover a piece of history.

As Director of Benefit Verification, Kennedy Reynolds leads the team responsible for giving Centerline’s clients a clear understanding of patient benefits, eligibility, and payer requirements before treatment begins.

Since joining Centerline in 2021, she has developed a deep understanding of the complexities of behavioral health reimbursement, earning a reputation for accuracy, efficiency, and operational leadership.

Kennedy leads a team that works closely with insurance carriers and behavioral healthcare providers across the country to accurately verify coverage, interpret complex payer requirements, and provide admissions teams with the information they need to evaluate prospective patients. She understands that every benefit verification directly impacts an admissions decision. By delivering accurate, timely insurance information and a clear understanding of payer requirements, Kennedy helps providers confidently assess coverage and make informed decisions for prospective patients.

Outside of work, Kennedy enjoys spending time with her family and dogs, hiking, rollerblading, and working out. She finds that an active lifestyle brings a sense of balance and positive energy to both her personal and professional life.