VAT deregistration on death

An older accountant told me what happened to a client after they had died.

The accountant had notified HMRC of the death and deregistered the client from VAT.

Imagine the accountant's surprise to then receive been told nby the client's widow of a follow up letter sent to her deceased husband.

The VAT office letter said: 

"We are sorry to learn of your recent demise. We have processed your request for deregistration but if at any time in the future you become liable to be VAT registered again, you should apply to this office for a new VAT number."