Same issue here, the app-store tells me Testflight needs iOS 13 to install.
I had Testflight running on 12.5.1, I changed AppleID and deleted the iPhone (6) to reinstall, apparently I should have kept settings and data when I changed the ID, if that had helped?
If anyone have an idea on how to continue doing tests on older hardware, please share.
LukS
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
Last seen
User for