2 minutes ago, HighlanderICT said:

OR - is it better, or even possible, to do it the old-school way and upload the new version files via FTP and have the site recognize a new version needs to be installed

Yes, you can do this. Download a full set of files from the client area. Upload them to your site (make sure to overwrite everything).  Once the upload completes, visit domain.com/admin/upgrade to kick off the upgrader. 

I would recommend making a full backup before you begin just as a safety precaution!

It wont corrupt your themes. it's a measure to temporarily disable things, in order to get you back in

thank you, this did work and no themes were adversely affected in the process 🙂