Hello. I am Keith. one of the experts on Just Answer, and pleased to be able to help you with your question.
It is a general proposition within UK taxation that an individual is responsible for the cost of getting from his residence to his normal place of business and that he can only have one such place. In this instance there is no such regular place of business as they operate from home. So this should not have been declared on the P11D as a benefit in kind. If this form requires amendment for previous years then the ball can be stated rolling by simply writing to the tax office concerned seeking to adjust prior year positions. HMRC may well adopt an approach that the studio to which the individual travels the most is his regular place of business and disallow that travel.
I do hope that I have helped resolve your conundrum.
The gross private mileage usage is the matter to be disclosed in the P11D.
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