VT Santander Consumer Finance

VT'ing my PCP tomorrow and wanted to know the process if anyone has gone through it with Santander CF.

Do I first need to call them to state I would like to VT, and then submit a letter/email confirming it?

And once I VT, do I need to keep the car insured and taxed before someone collects it? As I need to swap over my car insurance onto the new vehicle (subsequently leaving the old vehicle uninsured).

Appreciate any help on this.