Perhaps you should finish the new build per the terms of your planning permission, assuming a finish was called up on the elevation.
Some local authorities can be particularly "picky" in certain areas considered sensitive.
Choice of colouring agents should allow you to get whatever colour your like, or you could paint the finished dash.
Colouring agents can sometimes vary with the batch no. of the agent and the specific mix of the dash, so be wary.
You can also get a dry dash, but this required a huge amount of skill to put on to have it look consistent and "even".
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ONQ.
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All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.