Not the best day to arrive at Heathrow?

Uh oh.  My current schedule has me landing at LHR Wednesday morning.  It appears that could be trouble...arriving during a labor (labour?) action by a number of UK unions, including the border officers.

BAA (the privately owned airport operator) has publicly written to all the carriers advising of 12 hour queues and are asking carriers to run flights at 50% loads.  Their letter is here.  Not good.

Barring the action getting called off, I think I may call off my trip!