CSLM10161 | FAQs: employers questions and answers: stop notice: when do I stop deducting?
From HM Revenue & Customs · Collection of Student Loans Manual
Suggested answer
Only when you receive a Stop Notice or, exceptionally, when you receive instructions from your Tax Office.
Upon receipt of a Stop Notice, follow the instructions on the Notice and stop making deductions on the first available payday after the stop date shown on the form.
HMRC action
None