Find out who made a change to a Sign-up Sheet

I know this has come up in the past, but can anyone in the TT support team tell me who has touched one of my sign-up sheets? “2016 Popcorn Bulk Order Pickup” – all the “Tasks to Complete” but one disappeared.

Very frustrating as I just sent out the announcement yesterday after it was setup, and of course put a newsletter announcement about it.

I have to put the items back in, but I would love to know exactly which of my users modified it.

And I have scaled back who has access to manage the sheets.