I updated yesterday to 5.12.5 and I am so glad it has fixed my horrible battery drain I got when I updated to 5.12.4. This is on my Oasis3. Or 10, or whatever its called. The latest one. I updated my Voyage and baby Oasis also, but can't say yet if there was a battery drain on them or if it got fixed. I don't use them much anymore.
On 5.12.4 I had to charge my Oasis like twice a day. I could look at the percentage and watch it go down. Like I got up to get my tea and came back and it was 2% down. Wasn't even a minute. I would read a bit and go from 99 to like 64. Horrible. Now I am back to before, or even a bit better maybe. I read for 3.5 hours this morning and a bit before bed. I had charged it to 99% before I went to bed. So overnight and this morning session its at 90%. Wifi was off.
For some reason my Oasis doesn't charge to 100%. It stops at 99%. Sometimes it stops at 97%
But anyway, just glad that mess is over with. Otherwise so far it looks the same as 5.12.4 for now.