121.This section provides for the amendment of a tax return by the taxpayer and allows Revenue Scotland to specify the form and content of any notice of such an amendment. It sets out that the taxpayer must make an amendment within 12 months of either the filing date (which is defined) or any other dates that the Scottish Ministers may prescribe by order (and different provision may be made for different devolved taxes). The power for the taxpayer to amend the return by notice under this section does not apply where sections 87 or 93 apply, which involve Revenue Scotland making its own amendment to the return either during the course, or on completion, of an enquiry.