How long should I wait to try to re-enlist after having been separated for failing the APFT?

How long ago did you get separated?

At least wait till you can meet the standards. If they will let you back in.

for most chapters its 2 years. Im sure there is some waiver out there from your recruiter.

Call a recruiter for specifics and possible waivers depending on your RE-Code. It sounds like you were a chapter 13. Good luck

You will need to pass the ACFT now. The APFT is no more. Jimena Rivera

What have you been doing since you separated to get better enough to pass the test?