Order of stay will be vacated if an appeal is not disposed within the prescribed statutory maximum period. The amendment substitutes the third proviso to section 254(2A), providing that if an appeal is not disposed of within the period allowed under the first proviso or any period or periods extended or allowed under the second proviso, and those extensions in aggregate exceed the statutory maximum, the order of stay shall stand vacated after expiry of such period or periods even if the delay is not attributable to the assessee.