What is the authority used for a modification after award, which fixes an admin error for a change to a construction POP.  This error was realized after award and based on the Govt. answering a PPI for additional time needed by the contractor.  The TO was awarded with the original time not the agreed to time.  

Standard Form 30, block 13, says to use 43.103(b) as authority for an administrative change.

But if you issued a task order that stated an erroneous period of performance you should prepare a supplemental (bilateral) agreement rather than an administrative change, state in the mod that the change was made to correct an error, and get the contractor to sign it.