There have been some very useful points made and no doubt they may well be useful to others who may stumble upon this thread in future.
Personally, I am somewhat 'old school' having started my computing on a Nascom II with no disc drive. When I did get a single side 170k floppy drive (5¼"), there was no Operating System - just the raw 'Go to track X sector Y, read 128 bytes' and with that I wrote a point-of-sale system to control my DIY Supplies shop!
I've never had any truck with MS OneDrive, GoogleDrive or any other such application - well not since I had a disagreement with a Western Digital 'OneDrive' system which thought that it knew what I wanted to do better than I did!
- - - I do have 'SyncBack' which has been dealing with backing up of many drives over many PCs on my network for many years but I would certainly not want any of my data on 'The Cloud' !!
I should have appreciated @Circular's point about creation/modified date as well
I'll simply keep my eye on the dates before I open any project - how long that will be remembered is to be tested
Thanks for all the input.