Thank you @Carlos-Anso
For GrapheneOS, no, I've trusted your organization enough not to haved used the ADB SHELL on any of the two phones listed above. The boot loader was locked after initial install of Graphene OS as well per instructions. They are both stock and received regular updates (for the 4a it's on whatever pushes come from the extended support updates). I am very familiar with side commands in the ADB SHELL. Since I've not had an issue to debloat a GrapheneOS phone, I haven't resorted to pulling out software ever/yet.
Again, per creating a fair baseline - I'm unsure if any charging issue may have caused this issue for both phones in the same week - without knowing what logs to gather, I can't provide any additional information for troubleshooting. I won't continue to hyperfocus on the update as the cause since I would like to replace the ports and batteries in both first. The only logical baselines I can offer is to replace the traditional source of known hardware issues for these models of phones, the ports and batteries - and then use the pro-offered Google chargers for these models. One phone charged from a conditioned power supply, the other phone was on it's on standard USA 15 V 125 V outlet (line tested good for informational purposes and is properly wired per the check I did with a Klein Tools GFCI Receptacle Tester). The chargers were vendor provided, I do not know if they subbed any third party parts, just the chargers they came with from the retailer.
At this point, until I have better evidence, I will tenatively withdraw my assertation that it may have been an update. After reading through the comments provided by your group on this thread, it only makese sense to reduce known causations for this issue.
As stated, the only way I can know for certain is to replace the aforementioned parts, standardize the charging conditions and create a baseline that is fair for troubleshooting.
Additionally, the Pixel 6 (ordered and en route) will only charge from the provided charger/cable - if it occurs again on all three devices (the two going into the shop this coming week days), I would like to go further into this issue with the Graphene Forum to isolate causes.
Appreciate your response.