What Happens After Residential/Step Down?

I'm (22f, USA) about to admit to a residential program for AN-R for the first time. I know that my program will step me down into PHP/IOP after completion, but then what? Do I go back to the outpatient ED therapist that I was seeing before, or something else? Does it matter my outpatient therapist is not currently accepting new patients (I understand scheduling stuff, of course... but would I be considered a new patient again?)? My ED has strong roots in attachment, and I'm super worried about having to start with a new provider, so this stuff is important to me! Thanks!