I must say I too got busted on guard today, was beautifully annunciated, only for someone to come back and say "....aaaaaaand you're on guard" A polite, "......awwww thanks" and I was on my way. Partly due to chatting to mates on numbers then switching back to 121.5 without transferring tx to the other comm. No biggie.
Long Live the guard police
j3