Hanover and Cumberland

The Queen accepts the Prince of Hanover as being a Royal Highness,
though the german government long ago abolished the HRH. She used it
when she gave the assent to his marriage with Caroline of Monaco.

If the Prince of Hanover were sucessfully to petition HM for the
restoration of the Dukedom of Cumberland and Teviotdale, would he be HRH
the Duke of Cumberland and Teviotdale, or His Grace the Duke of
Cumberland and Teviotdale?
Naturally HM could specify whatever she wished by LP or RW or court
circular, but if she simply restored the raw peerages, what would the
style be by default under UK law, given that HM has already accepted
that he is an HRH by birth, but also that his HRH is not british?

CJ Buyers...

One assumes that anyone whose peerage is being restored will either be
referred to or addressed by HM. The answer to your question will
consequently be plain at that time. The chances are high that having
addressed him as HRH in official documents, he will be so addressed
subsequently. Whether he is termed a "Prince of the UK of GB & NI", is
less clear.

Carsten
(pounds to pesos someone is going to start an argument that the PoH is a
british HRH)

the_verminator...

I suggest she grant him the style of "His Royal Grace, Ernst of
Hannover, Duke of Cumberland and Teviotdale".

That would put the cat among the canaries!