I am preparing an app for ad hoc distribution via Test Flight. I have stepped through (successfully) all of the preparatory steps in this Ray Wenderlich article already (https:
I let this run for a long time (basically while I went out shopping). When I came back it was done. So for whatever reason this just takes a really long time to do.
That said, it was also the incorrect action. The way you add testers to TestFlight since Apple bought it is different. Now, instead of exporting and uploading an IPA file, you have to submit it to the store and let it be reviewed by Apple before you can add testers.