The OP has to do more than “show...his TSA credentials”. There needs to be a TSA training request/authorization specific to the flight school. More than likely that’s going to be the show stopper.
Oh, that is a complication.
I just now looked up the AOPA page explaining how to get authorization
https://www.aopa.org/advocacy/pilot...s-and-non-us-citizens-seeking-flight-training
and the TSA page
https://www.flightschoolcandidates.gov/home
It's clear that the student and the school both have to use the TSA website to apply for approval for instruction.
And it's clear that it's possible for the student to switch from one school to another by submitting a new training request to the TSA. Excerpt:
Once a training request has been submitted and accepted or rejected by a provider, you cannot transfer or reuse the training event request.
- If you have submitted a training request and later make a decision to train with a different provider, you will need to submit a new training request.
- Your previous flight training provider committed to comply with TSA regulatory reporting and recordkeeping requirements by accepting your previous training event request. That is why your training request is non-transferable.
But it's unclear whether the student can have two simultaneous training requests, to provide authorization at two schools simultaneously. (For the purpose of preventing another 9-11, it wouldn't make much sense for the TSA to block someone from getting instruction from more than one place at a time, but not everything they do makes sense, so who knows.)
Edit: the TSA page has contact info. Maybe the OP can just contact them, to ask the specific question, is it allowed to have training approved at two locations simultaneously.
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