GST rule amendment updates signature verification, deemed registration timelines and revises registration and composition forms. Amendment modifies procedural requirements to allow documents and certificates to be duly signed or verified through electronic verification code or other notified modes including esignature; it inserts a deemed grant of registration if a certificate is not made available on the common portal within fifteen days and no notice is issued, revises form entries including substitution of 'Provisional ID' with 'GSTIN', clarifies composition categories, and updates cross references and proviso omissions in the CGST Rules.