VATREG02450 | Basic principles of registration: supplies made by a taxable person previously registered
From HM Revenue & Customs · VAT Registration
In determining liability to registration under VATREG18000, the value of a taxable person’s supplies made during the period of a previous registration is to be disregarded if:
the registration was valid, and
you are satisfied that, before the registration was cancelled, the taxable person had given us all the information we needed in order to determine whether to cancel the registration.