Thanks so much Mike - Sierra seems okay with DP, Reason (with Rewire), and Bias Peak Pro 7 but I wanted a get out of jail strategy with the option to go back to El Capitan - clearly something the Apple "geniuses" couldn't help me with. I will be testing Sierra with DP properly today (had one crash early on after initial upgrade to Sierra but then it settled down) - but it is good to know you can go back to the previous backup - which is what I thought Time Machine was for. Its good to know as always that someone on this forum has the knowledge. I may trouble you for more information on the backup if I find I need to go back. Thank you.mikehalloran wrote: Nah.., You need to do do an Option-Boot and do a complete Time Machine restore making sure it's from a backup that precedes the upgrade. It will seem to take forever to select the right backup but it's in there.
When I update my OS, I always turn TM off beforehand so that it's easier to restore if need be but it's possible in any case.
There's a way to create a USB boot drive in Terminal for any version of OS X. You would boot into it, use Disk Utility to format your boot disk for the OS you want, install the OS then use Migration Assistant to bring in your settings, files and applications. Again, use a backup that predates your Sierra update. I don't have it on my iPad but can post instructions if you need.
Gary