GST registration procedure for provisional PID holders enables migration completion and mapping to a new GSTIN after portal application. Specifies a special registration procedure for taxpayers who received only a Provisional Identification Number (PID) and did not complete FORM GST REG-26: furnish prescribed details to the jurisdictional nodal officer, apply on the common portal using FORM GST REG-01 after GSTN email, obtain approval with ARN, new GSTIN and access token, send new and old identifiers to GSTN for mapping, and perform first-time login with the old PID to generate the registration certificate; such taxpayers are deemed registered with retrospective effect.