Ask an Immigration Solicitor. Get an Answer ASAP.
Please do not ignore. You should write a letter to the Home Office explaining why you need to extend but make it clear you are not extending beyond 6 months. Provide supporting evidence of why the change of date, a copy of your visa and when you plan to leave.
There is no email. I have informed what you need to do.
You will not receive a response but keep a copy of your letter and receipt of postage.
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