RBNgate spot without alert?

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1

I just chased HB9BIN/P while operating /P not SOTA.

To my surprise, I notice now (a few minutes later) the following spot

Sat 12:17 ON6ZQ/P on ON/ON-016 7.032 cw
*CQ CQ at 30 wpm. S/N=21 dB at HB9DCO {Via RBNGate} (Posted by KU6J)

despite I have no alert posted at all.

Any clue as why this happened ?

2

I guess it might be down to an (old?) alert with an extended spotting window (as mentioned in this thread )? I suspect only @KU6J can say for sure, though.