Tax migration procedure for provisional ID holders: apply on portal, map new and old IDs, complete registration and generate certificate. Specifies a special registration procedure for taxpayers who received a Provisional Identification Number but did not complete FORM GST REG-26 migration: taxpayers must furnish prescribed migration details to the jurisdictional nodal officer, apply on the common portal in FORM GST REG-01 after receiving an e mail from GSTN, and, after approval, submit the new GSTIN, access token, ARN and old GSTIN to GSTN for mapping; upon mapping taxpayers must use the old GSTIN for first time login to generate the registration certificate and are deemed registered with effect from the commencement date in the notification.