So have been testing the phone and in particual how to use Google Fi, after a lot of trials I found that I could get it to work and fully activate it
a) In order to make things to work I had to use a v33 APK for Google FI, it seems that recent APK have certain limitations that created a lot of issues to activate
b) Had to perform multiple setting changes:
- Had to change battery to high performance
- Ensure that gmail was the default account
- Permissions, had to activate all, including single permissions
- Had to turn off 5G in the mobile network portion and click on for roaming
- Had to trun off optimized on the flow control within mobile networks
c) Don't let the APK be updated by play store updates
d) Under mobile networks you will find 4 APN's , I selected the one with T Mobile in the description
The whole thing works great with no issue including 5G, but ( yes there is one) I noticed that in certain locations I would lose phone/data, I could not access mobile network screen ,etc. Going into airplane mode would not work and had to reset the phone. This would occurred randomly
In order to test I used a SIM from Mint Mobile as to test, no issue and stable at al moments
What I found is that I was moving around the town, the phone of course due to roaming , move between networks . Noticed that if I restricted roaming phone would stabilize
Speculation:
My assumption is that all phones roam between networks and in this case I think at times you will need to roam on maybe within an AT&T portion of the network and the phone is left hanging creating this gap and as such the phone falling in this loop
APN's between Google FI and MINT area the same with exception of the MMSC and MNC (260 vs 240)
If someone has figured out an improved way to have Google Fi 100% and in particualr having a consistent behaviour please share so we can help others