There should be no change with Brexit with regard to taxation, as taxation has always been beyond the remit of the EU.
The fact that you pay UK tax on your medical pension is correct if it falls under the “government pension” category, and this will not change after Brexit as it is governed by the UK-France double tax treaty, which is nothing to do with the EU.
You will also continue to receive your exported DLA because the Brexit Withdrawal Agreement treaty states that you should do so.
This is still to be clarified for Britons who move to France after the Brexit transition period – but this is not your case.
Like other Britons living in France, you will be required to make a simplified carte de séjour application to obtain a “Brexit deal” card, at the latest by six months after the end of the transition period.
Unless the transition period is extended, the deadline therefore is June 30, 2021.
Reader's query answered by Hugh MacDonald
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