I know that this is an old post, but my question is relevant, otherwise I'd post it as a brand-new question.
Is it absolutely necessary for Apple to approve beta builds that are only going to be used by a handful of testers? I pushed a build to TestFlight the other day, and it's a beta of an app that exactly one person is going to use - an app that is being tested on a whopping TWO devices (my iPhone, and my client's iPhone). It was after hours, and I'd have liked the client to be able to take a look at the app that evening, but I was stuck waiting for Apple to approve the build until the next day.
I understand the need for approval when you release the app to the App Store. You get queued up for review and approval by Google, too, when you submit Android apps to the Play Store. The policy makes perfect sense for apps that you're releasing, that you are ready to unleash on an unsuspecting public :)
But it makes no sense to make developers and testers wait for approval for a beta (or alpha) build. And in this particular case, I became annoyed with the App Store beta process, and moved testing from TestFlight to Microsoft's Visual Studio App Center, which makes new test builds available as soon as you upload them.