OSX 10.15.6 was a bit buggy. I updated my mac, and while working on normal power, it seems to work fine. No problems, no bugs.
I started to work on the battery and time after time, computer just stops. just restarts when I came back to my desk, or wanted to browse or see mail, and ………. nothing. Just frozes.
So, reset NV-RAM did not work, reset SMC did not work, called apple care, well, they gave me the standard points first while I already knew and tried. So, I was sending in reports and keeping my mac on regular power… until… new update 10.15.7.
I installed it. I kept my breath, and kept it and kept it.. Hmmm.. Needed to breath. no more freezing. Pfffff.. YEAH I CAN WORK AGAIN!
So, now you can update. When you still find some weird points, first thing to do is reset the NVRAM and SMC. For SMC you need to check which version of hardware you have. with or without T2 chip.