If you are a big enough, politically-powerful customer, like MARCS doing their LLA rollout, Moto will sometimes make special exceptions and sell you upgrades to EOL radios (even for XTL).
A random dealer? Unlikely.
As for service contracts, you can check the serial number lookup tool in CustomerHub to see whether your radio is under any sort of special service plan still. But in general, if it were, you (or your contracted radio shop) would know it, since it would have been specially negotiated with Moto.