Hi Hannah,
I'm really sorry to hear of your infiltrative BCC on the tip of your nose. Firstly, I want to say - brace yourself for a longish journey, but there will be an end to it!
Two years ago I had the same diagnosis, also the tip of my nose. They took off a piece that was 28mm across down to the cartilage. At the time, no plastic surgeon was available and because of the size, the dermatologist doing the procedure didn't feel confident doing a skin flap. As the piece was too large to take from e.g. behind my ear, he took the graft skin from my clavicle, which is the best you can do if not using skin from your face, but it does look slightly different. The graft has healed well, but I'm left with an irregularly shaped, different coloured and textured piece of skin covering my nose tip.
This morning I discussed possible revision surgery with a plastic surgeon. He confirmed a skin flap would have given a better result and said he could take off the graft and do a local skin flap. I would have to go private as the NHS (I live in the UK) would not pay for this. An alternative would be medical tattooing, which I'd never heard of, but which I'm now looking into.