Looks horrendous. Like a regular terrace street scene, but one of the houses has a tumour, or several tumours. That said, at least the materials used are not offensive (apart from the dormer).
Such dormers would be a permitted development - a Certificate of Lawful Development.
However, yours is already built, so you can apply for a Certificate of Lawful Development (retrospective), however before doing that make sure it complies. If it does not, and make the CLD application, and planning visit they will refuse it.
If there is any chance that it does not comply I suggest you cross your fingers and wait until the four years is pass and apply then.
If its 49m3 then it does not comply, do you have a 200mm setback from the eaves?, Do you have the evidence to verify the application?
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