Experiencing exactly the same issue. Started happening randomly last Friday - 9th of April. Previous builds till 8th of April did not have any issues.
Tried clearing all caches/derived data folder. Regardless whether archive was built and uploaded using fastlane script or using Xcode, after submitting build for external Test Flight group, immediate e-mail is received "ITMS-90433: Invalid Swift Support ..." and build status is switched to "Invalid Binary".
pauliusg
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