There's a small 'oh', both understanding and not - it wasn't exactly a nice time, but... - and then as the question is asked, he has to think.

"Hmm, about..." But this takes times, a click of his tongue as he fails to think. "I dunno... it was way back." It had to be, right? "Maybe... before the third mission? Or after? That'd be three months in..."

He tries a few seconds more, before sighing. "Sorry, you should ask the others. We get a mission every month, so those're easy to follow. But the storm was a single day."