DST aftermath

It is inevitable that there will be some computers across our 20 + customer
environments that will not get the required DST updates before DST starts on
Monday at 2 am. (ie. users comming back from vacation, loaners, un-reachable
executives, etc.)

If we apply the XP DST patch to a machine next week, if the Exchange mailbox
has been scanned, in theory will that resolve the problem? Or, at that point
will things be messed up and we should expect to have to take other remidial
actions?

TIA,
John