The OTA has been paused until further notice. Google is looking into the issue and is going to get the issue fixed. It won't be releasing any further information until it figures out what caused the problem.
If you have not updated your Pixel smartphone to Android Q Beta 4, then you may want to hold off. Even though the OTA won't come to your device now, it is still available to download on Google's website. Given the fact that a number of users - a pretty large group actually - haven't been able to update their Pixel devices. It's a pretty big issue.
After downloading the update, the Pixel will restart, however once it has restarted, some users are getting a notification that we have never seen before. The notification says that it "Couldn't Instal System Update". Which is a pretty odd notification to see.
Update: A/B PARTITIONS SAVE THE DAY!
A few reboots and it's back.
I have never seen this notification before. pic.twitter.com/LImvmdXj6x
— Ron Amadeo (@RonAmadeo) June 6, 2019
The good thing here is that Google is aware of the issue and is working on a fix. But who knows how long before that fix is available. Considering this is supposedly the last beta before the two release candidates come out, this is a pretty big deal for Google.
This goes along with the rather rocky road that Google has been on with Android Q. With the second beta for Android Q, it actually had to issue another update, because the beta was so buggy and sluggish. Obviously, betas and previews are going to be buggy and sluggish, as that's the nature of the beast. So it really tells you just how bad it was, that Google had to issue an emergency update for a beta - let alone one for the second beta.
However, this issue likely a pretty small one. But trying to find the issue is going to be tough for Google. As this isn't happening to everyone. The tweet embedded above shows Ars Technica's Ron Amadeo having issues updating his Pixel 3 XL, which showed that weird notification. However, my Pixel 3 XL updated to the fourth beta with no issues whatsoever, so it's going to be a bit of an issue to actually find this issue and get it resolved.
This is why Google does betas though. Could you imagine this happening once it rolled out Android Q to all the Pixel smartphones on the planet? That would be a much bigger issue. This is still a pretty big issue, but the group of people that it's affecting is much smaller. Also, the group of people that are running the Android Q beta is much smaller, than those that own a Pixel - which is also pretty small.
Hopefully, Google is able to resolve this pretty quickly, and get the update rolling out once again.