You could add code to identify changes it the format and then handle the error gracefully. However, I would rather go back to the vendor and stress to them that proper upgrade procedures need to be followed. This means informing their customers of pending changes and then giving them the opportunity to run some tests prior to the change being implemented. Pretty basic stuff. Sounds like you may need to be speaking with someone higher up the chain of command at the vendor. I would push the vendor to fall in line and fix their enhancement/revision process.
