probably wont work as the new car will not be on the Motor Inusrance Database system that the DVLA use to check for insurance. Insurers normally update new cars once a week. Pain! My dealer got my tax without a covernote?! Don't know how they do it, but they did!have you tried taxing it online ?
+1, yes some dealers offer this for precisely this reason.You can take out 7 days free insurance from your HPC.