My NAS's latest TM backup of MBA2013 is seven months old. I've had the MBA2013 at work away from the NAS so it hasn't had a chance to connect and do TM.
Resuming the TM backup now results in:
Time Machine couldn't complete the backup because FileVault
was encrypting or decrypting a disk. Backups will resume once
FileVault finishes.
Not sure how long that will take. Maybe FileVault is what was freezing/delaying the partition merge in Disk Utility as well?
The tax information isn't in the TM backup, it is on the Boot Camp partition. TM doesn't backup up Boot Camp.