What is the future for people with face transplants as they age?

Unknown. However, there two factors to consider: 1) the natural aging process and 2) the possibly effects of chronic rejection. Given face transplants are in their infancy, it remains to be seen how this will play out.
Unknown at this time. Good question. There has not been enough accumulated information on successful face transplants (about 5 years) to accurately answer this question. One can speculate that the aging process will continue, although this may be accelerated or retarded by the ongoing use of chemical immunosuppression. One would hope the facial grafts last decades.