I wouldn't read anything into an instructor not putting a fuel cap on quite straight. We are all human.
What were you doing in France on a training exercise? Did you request to do the trip or something?
Seem of dubious training value to plod across the channel on a navex when you could be flying a leg with a map in one hand whilst negotiating to traverse some controlled airspace and then get a diversion. Lunch in France sounds like a jolly day out for the instructor with some training value thrown in as an afterthought.
Would make me suspect the standards are slack if it is routine for low time students on navexs to end up taking Lunch in frogland.
You did have a dinghy on board I hope? Or were you wearing a drysuit?
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