ios - What is the UX when I add additional builds to an existing external beta test in iTunesConnect -

i have app on itunesconnect few hundred external beta testers using it. important note, have 2000 testers end of month. want push new builds app- , this, i know how do.

what don't know is, what expected behavior beta users when add new build?

our company cares lot user experience, , don't want have our current testers of our current build open version they've installed, see crash because added new build i'm hoping update current version automatically.

apple job of making developer think might happen. i've searched everywhere find answer in docs- please help! after selecting newly approved build switch in external testing portal, upon selecting save, alert appears:

(405 first build, 407 new build)

so, happens when save this- users notified need update app?

will "update" happen automatically them if they've installed first build?

if open installed version, crash?

if so, can prevent happening?

my team want send out 1-2 builds / week (of same app, fixes , improvements) same group of testers until we're ready officially launch app. i'd hate think crash app on them every time. far know, there no way me test before performing action- i'm added internal tester, that's different ux in testflight (builds made available internal testers after uploading)

if think has been asked already:

this not duplicate of this question- because haven't attempted send out build yet. want make sure linked issue not happen testers!

my question unlike this one user did not know how increase build number, unlike this one, referring testing new build of app has version in app store, unlike this one refers bug in app store user couldn't initiate external test after uploading build, , unlike this one user didn't know how itunesconnect portal works.