George is already nine years old, I doubt he will be alive in 2120, let alone 2140 (that would require him to live till 127 years of age). You have to rethink your math here. If we assume he'll die at 100, that brings us to 2113.
>>988747+(OP)
Ah yep. Forgot to include another 'skip' generation of either abdication or short reign like Charles will be, since my assumption was that William serves a term similar in length to his grandmother.