In reply to balmybaldwin:
Go for the 20GB Photography Plan at £9.98/month and use 'Lightroom-Classic' = desktop LR
You also get desktop-PS and 'cloudbased' LR (but with only 20GB online storage). I don't use the cloudbased-LR.
https://www.adobe.com/uk/creativecloud/photography/compare-plans.html?promo... 3
Desktop LR-Classic is currently at 9.2.1, so a few on from your LR6 (2015). You'll have to update your Cat(s).
Your original Cat(s) will remain unchanged - Lightroom will create updated cat versions that you will have to use on LR-Classic.
Any previously edited RAWs will be based on the LR-6 raw conversion process engine (Develop-Calibration-Process) - not sure what LR conversion engine that used (I think its Version 4). Its now at Version 5. If you want your old edits to use latest conversion engine, then you will need to update the images (can be done in bulk via 'Sync' images, but only just check the 'Process' box ! ... try it out on a few images ....)
They'll also be some new Develop features that will be at Zero/Default on previously edited images.
... but I think you might have to update the Process version of an previously edited image to get to new LR Develop features ... you'll need to experiment/check