Warehousing extension for non-deteriorating imports may be granted for longer periods where condition and interest realisation are assured. The proviso to Section 61 permits extensions of warehousing for goods not likely to deteriorate, with Chief Commissioners empowered to grant further periods as they deem fit. Circular No. 47/2002 allows Commissioners limited extensions and directs that Chief Commissioners may grant additional extensions, generally in short increments, provided goods will not deteriorate and interest accrued has been realised. For categories including imports for shipbuilding and manufacture-in-bond units, Chief Commissioners may consider granting longer extensions than routine increments when satisfied about condition and interest realisation, subject to the overall maximum warehousing period under Section 61.