125.This section set out the procedure the Authority must follow when it proposes to exercise its own-initiative power to vary an authorised person’s Part IV permission. If, having regard to the ground on which it is exercising the power, the Authority considers it necessary, the variation may take effect immediately  or on a specified date. If no date is specified in this way the variation will take effect only after the time for referring the matter to the Tribunal has expired and any reference (and further appeal) has been finally determined (see the definition of “open to review” in section 391(8)).  The Authority must give the authorised person a written notice which gives the details of the variation, the date on which it takes effect, the reasons for the imposing the variation and for the choice of date. The notice must also inform the person of his right to make representations to the Authority within a specified period, and to refer the matter to the Tribunal.
126.Subsections (7) to (10) require the Authority to give further written notice of its response to any representations which are made.  This can be a decision not to proceed with the variation (or to cancel it if it has already taken effect), to propose a different variation (in which case the original notice procedure must be repeated), or to proceed with the variation (in which case the person concerned has a further right to refer the matter to the Tribunal).
Commentary on Sections Part Iv: Permission to Carry on Regulated Activities Section 53: Exercise of own initiative power: procedure