Where is my boot drive?

I'm using High Sierra 10.13.2 beta 4 and im having the following problem:

The disk formats correctly and HS 10.13.1 installs from my installer disk.

The system boots fine and I run Migration Assistant to migrate from my backup.

Reboot and alls well. I run from the Mac partition and shut down with no problem.

Restart from my backup drive and everything works fine.

Shut down and restart. No startup partition or recovery partition.

Run backup again and check diskutil and see disk0s2 in place of my startup partition.

drive info shows 720GB, not mountable and partition renames to FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF

Whats going on here? This has been happening for three days.

Have replaced my SSD with a new 1TB SSD.

Thanks in advance for your input. RonFisk...