VATREG19050 | Exception from registration: general
From HM Revenue & Customs · VAT Registration
A person can only be excepted from registration if
they have become liable to register on the basis of their past turnover (that is, they have exceeded the threshold in the past 12 months), but
they do not expect to exceed the deregistration threshold in the forthcoming 12 months.
A person whose supplies are expected to exceed the registration threshold in the next 30 days ‘forward look’, can not be granted exception.