Starting pointe is like starting ballet or pas de deux all over for the first time. It was the most physically challanging thing I think I've ever done.
For adivice, I would say GO FOR IT! You have nothing to loose (except maybe a couple of toenails) and everything to gain. If they are auditioning for a part that may involve pointe, you can say, "Been there, done that!" Experience is always a good thing.
I doubt I will be able to do pointe again. A lot of work from HERE to THERE for me. But if given the chance, I'd tie on those satin shoes and do it again![/i]