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AUC8 BIG update for U.S. Snapdragon S21 series, camera & April security patch


Extreme Android User
Aug 17, 2010
Cotswolds, England
This latest update is the 2nd for the Snapdragon U.S.A. country variants.

The AUC8 update is rolling out for the U.S.A. Snapdragon carrier S21 series models, SM-G99*U, (carrier locked), and SM-99*U1, (carrier unlocked).

It is a big, circa, 1GB download

[UPDATE] Releases so far, as of 13.00 hrs, UTC, 13 April 2021...

U.S. devices, SM-G99*U1 (carrier unlocked)
  • Cellular South
  • USA (generic) CSC code TMK
  • USA (generic) CSC code USC
  • USA (generic) CSC code XAA
  • USA (generic) CSC code AIO
  • AT&T
  • Comcast
  • Bluegrass Cellular
  • Verizon
  • T-Mobile (USA)
  • Nextech/C-Spire
  • Xfinity Mobile
  • Sprint (cdma)
  • Tracphone

U.S. devices, SM-G99*U (carrier locked)
  • Xfinity Mobile
  • Comcast
  • T-Mobile (USA)
  • Sprint (cdma)
  • Verizon
  • USA CSC code USC

This is the 2nd stable update in 69 days
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Hoping for better battery performance. The March update did nothing. The S21 is pretty awful with 3-4% drain per hour doing nothing with the phone in motion (e.g. in a pocket). It's the sensor activity that drains the power. It's not any apps doing that. With the phone resting on a table it will still drain at least 2% an hour.

Installed the updated, rebooted for good measure, now trying the resting power drain test. update: 5 hours 7% drain with the phone sitting on the sofa (sent and received two texts). Update: 10 hours sitting on the couch, 16% drain. I'll let it sit unplugged overnight. Essentially I have been keeping the phone plugged in 24x7 due to sensors draining the battery. It would be nice to carry it around instead of leaving it plugged in.

Update: 22 hours 30% drain. Phone sitting still on the sofa. I guess that's a little better than it was. I'll have to test carrying after I charge it back up.
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