App Store updates are being throttled down

After posting a new version of our app, we used to have 80% of our userbase on the new version pretty quickly (usually 72 hours, sometimes less). Over the past few weeks, we've noticed that the App Store has throttled down app updates, and it now takes much longer for a new version of our app to reach 80% (approximately 15 days, so 5 times slower).

He is an update graph before:

And a similar update graph after:

We've published several versions over the past couple of weeks, and we've seen the same slow update behavior for all of them.

What could explain these differences ? At the time of this writing, the update graph has very slowly reached 80% and is now flat. In the past it would easily reach 90% (the last 10% were always slow to get).

App Store updates are being throttled down
 
 
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