So I did the following...
upon getting that annoying white screen message that there was an update, I did a swipe-down, and on the notification I did a long press, and tapped 'app info'. I tapped 'force close'. and the message disappeared.
But only temporarily... Sometimes it would pop up in 2- 3 minutes, at other times after a few hours. ...?
So after much deliberation and a modicum of trepidation, I rooted my phone -gasp
-. It was actually far easier than previous iterations to do so. I used the current method where you run the scripts off of the SdCard. The most annoying part was waiting for the re-formatting to exFat of the card.
Having root, I was surprised that 'disable' was not made an option when I once again tried to disable the update, so I did the following:
I first tried 'Titanium Backup', but "freezing" is not available in the free version. So I used 'App Quarantine' to, well, quarantine "SDM" which is the offending app. So far I have not had to use the more rigorous methods #1 or #2 you described; hopefully will not need them.
Thank you for your help!!