I said I am fine with it as long as they ask beforehand and give credit.
However, I feel it would be more logical to show their watchers the art they were given in a journal/poll instead, rather than resubmitting it.
With a reference sheet, I wouldn't mind them resubmitting it, as long as the proper credit is given. Not giving credit is a big no-no.
Like a lot of people, I never delete artwork from my page unless it's personal art, and I just don't want it seen anymore because it's so horrible. But all art that I've made for others will stay, in case they lose it and want it again.
I guess it just really depends on why they want to resubmit it.