Normy,

Did you have the NNLC on a trip that you were assigned while on reserve? Sometimes someone will call in sick for a trip, knowing full well, that they were going to get a line check. The line check guy will usually stay on that trip and if you got it on reserve (or picked it up in open time), you might have inherited the line check. I got one that way a few years ago, while doing a HKG to SFS leg. Or maybe it's just you.