Update WCS

I've been uploading images from 1 telescope, ATMoB MAO, for some time. Uploads go swimmingly. Until 11/1. Now some, which have all been plate solved b4 upload, show that WCS requires updating.

We have been having small problems with MAO's tracking, but I don't understand why this would cause red WCS warnings. When I update WCS using older images they all end up OK.

Any thoughts on what's occurring?

Peter

BPEC