OK, so status update.
When the customer wanted to switch back to exclusive Google Drive usage, we found he couldn't upgrade his account to the 2TB option no matter how we tried. He finally got that fixed today with help from Google. The solution was 2-fold. First, he had to update his Google saved payment sources to include a credit card that wasn't expired! And then he had to do it from his phone rather than the PC! He was told it was because his initial Google One subscription had been purchased from his phone! I find this restriction sort of mind boggling.
So now I have a dilemma. His existing Google Drive account has about 100GB of his data in the on-line trash folder. (Available for perhaps 2 more weeks before being permanently deleted!)
Meanwhile, OneDrive moved his data to the c:\users\user\onedrive\documents folder. (And equivalent Pictures folder). And this folder change is what triggered Google Drive that the data was deleted so it marked all the on-line versions as Trash!
Now thinking ahead, when I disable the OneDrive folder redirection and put stuff back where it belongs I think Google Drive will now detect that 100GB of data as "new" and want to upload it all again.
Or before changing folder redirection should I restore all the existing files from the Google Drive trash bin? Which will mostly likely result in Google Drive wanting to download all 100GB!?!
My theory is that restoring from trash will give Google Drive the opportunity to detect the files as unchanged when I fix the folder redirection and perhaps it won't try and upload everything again. And downloading should be 10 times faster than uploading!!!
What a royal pita in either case since I think his best Internet is 100Mb/10Mb.
And I'll be doing this via TeamViewer since the customer is in Iowa and I'm in Wisconsin.
Yes, I'm thinking I may need him to find some Google Fiber Internet he can "steal" for the attempts!