Minimally, with the current architecture, a firmware update could utilize a Jan 1, 2000 epoch value (vs. Jan 1, 1970) and push that date out another 30 years to 2068.
If by then and we start supporting double precision floating point values, Jan 1, 1970 epoch can give you a huge range, both in terms of years but also precision timing (e.g. July 4, 2076, 12:34:56.789012)