SG29950 | Security as a condition of releasing a VAT credit: returning or calling in security
From HM Revenue & Customs · Securities Guidance
You should return security when
the claim has been fully verified and repayment has been authorised
the joint and several liability is paid or withdrawn.
You should call in, or request payment of, security when
the claim has been verified and disallowed
the joint and several liability remains unpaid.