I did an unofficial post-bacc through UC Extension. Mainly because I'm not a URM, disadvantaged and apparently had too high of an MCAT (ironic huh?) to get into my school's official post-bacc program. Also didn't want to move away from this location, so no other post-bacc's or schools to choose, so did the Extension which cost an arm and a leg.
Ended up doing a PhD program, and taking undergrad courses as electives, which also count as post-bacc. Can't beat "free" education😉