Last couple of Thai Airways visits were 28th Oct 2013 and 13th Nov 1989.
For VS, we seem to have:
747: daily JFK, daily ATL and 12 weekly MCO = 4 based for 26 flights
A330: 2 weekly BGI, 3 weekly BOS, 3 weekly LAX, 4 weekly LAS = 2 based for 12 flights.
Aren't GLA-MCO and BFS-MCO 747 routes? That could mean they are using a MAN based 747 next year so you get 28 flights a week out of them.
MAN-SFO is 3 weekly. So either the route is getting reduced frequency or it's being culled as it can't operate using the planned A330 operations for the other routes.