I am creating a iOS application using Air 3.5 and flash builder 4.6
When I create a release build, it takes up to 20 minutes to create the ipa.
Is there a way that I make flash builder create a "release" build using ipa-test-interpreter instead of ipa-ad-hoc?
No, and don't try!
Release build and ad-hoc build and standard compile test-build _all_ recompile into native instructions that are faster to run, more robust and generally better.
Whereas, the test interpreter is a hodge-podge of stuff that runs dog-slow (when compared to properly compiled stuff) and will never be approved by Apple for release.
To convince yourself, maybe try running the two side-by-side and comparing; you will see that the test-interpreter runs way more slowly and less efficiently. Worse (or better) the test-interpreter also runs _DIFFERENTLY_ in some respects so that some specific functions that iOS doesn't allow todo with loading and displaying content can run in your test-interpreter even though there is no way in hell you could ever use them when packaged for release.
Yes, I know it takes an age to compile, and it's worse for the standard-mode compile as you do all that and _still_ get poor performance thanks to all the debugger plugin stuff, but really, the proper compile is by far the best result from all perspectives.
It's just the programming gods' way of telling you to go and have a cup of tea. (Or to buy a faster computer and stop for a quick espresso.)