Do you recall which version of Catalina you were running at that point? The last version was 10.15.7. This may be significant because it contained, for the rMBP10,1 and some other models anyway, a firmware update.Previously I was using Catalina - which also has sleep issues and was hoping to escape them by leapfrogging to Sonoma. Would I have to reinstall Catalina and then use OCLP to install Ventura or can I do this from Sonoma? Thanks again.
If you want to check whether the firmware is up to date on your Mac I highly recommend using SilentKnight - if you don't have it here's the link to the download selection page: https://eclecticlight.co/lockrattler-systhist/