Medway - how many Dashes went tech that day? I appreciate that the route you mention suffered, but out of a fleet of 20 odd aircraft it could then be put into perspective!
Out of interest, I think the difference between ATC equipment not going tech over night is that the equipment stays powered up over night and quite often kept used.
A Dash 8, sits on a cold apron, de-powered, getting damp and when powered up, electronics and such like, don't like it. Thats often why aircraft go tech first flight. It may have not been the case this time around but who knows?! I remember Air UK Leisure's first A320's which had come from a damp humid part of the globe ALWAYS went tech first thing in the morning!