Once had a call out at an ungodly hour when I was on a training course at a certain training establishment outside Weston Super Mud. We'd been pre warned by the course staff the day before, as the entire class were all JT and above from other stations there had been a hypothetical discussion around what a wonderful place this training station was but in the event of a war we would of course have to return to our home units by the fastest route.
So when the hooter went off we rolled over and went back to sleep until breakfast time, whence we strolled down to the mess in civvies. When we got stopped by a shiney Flt Sgt who wanted to know what we were doing the response was "about 70 up the M5/M6 on our way back to Kinloss / Leuchars / Coningsby..."
Then there were the Tacevals at Lossie in the 80's, the first on the day of the raft race and the second when the entire station was boltholed because they were digging the runway up
Then at 7:30 the hooter went again to announce the exercise was suspended, and would resume after the normal days training was completed at 17:30. Funnily enough we finished early that day and were in Weston by 17:30...