(This question was asked in the July 17, 2023 Livestream. You can find Brenda's full answer at timestamp 42:40 on that video, but we're copying it here for easy reference.)
ANSWER:
No. You can only register with one of the six options for compulsory attendance in Florida... and PEP is one of those options. Umbrella schools count as private schools under statute (a different option), and students enrolled full-time at a private school do not qualify for PEP.
You could take classes at a private school part-time while a PEP student (not as a registered student of that private school), but you would have to pay for it out of your own money and it would not be reimbursed (because although umbrella schools are considered private schools in statute, most umbrella schools will not have met the necessary qualifications to be considered an "eligible private school" for scholarship fund use under PEP).