In answer to the original question, yes, you are 100% free to cancel your order at any time, for any reason, until the point where you enter your PIN number at collection. Personally, with the demand and backlog of Allspace orders, I don’t think the dealer would have a problem moving the car so I personally wouldn’t be too worried about the morality of cancelling for a “minor” reason.
All that said though, as someone already said, the Allspace is a 5-8 month build time so if you DID change by cancelling and reordering, you’ll have to wait for the car.
My last car was a Black Peugeot 407SW and while it was hard to keep gleaming clean, it didn’t look that bad when it was just a bit dirty, but there are definitely easier colours to keep clean. I think someone already said this but I’m going to reiterate the sentiment. Every time you walk up to the car you’ll see the colour so if you’re really set against the grey, then you need to make the change or you’ll potentially have 3 years of regret and trust me, you don’t want that. I’m hopefully in my new car Friday and I’ve never been happy with the car I’ve had for the last 3 years – I should have stood up and refused to be convinced otherwise back in 2017.
"Man is born in freedom, but he soon becomes a slave, in cages of convention, from the cradle, to the grave."