That's the funny thing, they didn't call me on either contact number on my MPD account - they called me on the "existing number" I provided when applying for the T-Mobile contract.

Presumably that is the number which secures my new contract credit check (basically T-Mobile didn't have to do one as I already had an active line with them) so kinda makes sense to use that one I suppose.

Status still on "Ready to Despatch" though and no new line showing up on my T-Mobile account yet. Still, now the money is out I am pretty sure it will ship as promised.