Education Minister Chris Hipkins' press secretary Richard Trow said yesterday the deadline had been extended from March 27 to April 5.
He said the Tertiary Education Commission was informing industry training organisations and institutes of technology and polytechnics.
Opposition to the proposed merger has been widespread, especially in Southland and Otago where the Southern Institute of Technology and Otago Polytechnic are considered model institutions.
Otago Polytechnic's chief executive Phil Ker welcomed the announcement.
''That's good. Of course we are pleased.
''I think it's an extra 10 days to get better submissions together.''
The polytechnic had been focused on the aftermath of Friday's shootings, rather than its alternative merger proposal, for the last few days, and that would continue this week, Mr Ker said.
''I think everyone has been distracted.
''It's still hard to believe really that something like that could happen in New Zealand.''
The polytechnic's main concern had been providing support to its alumnus, Dunedin man Mustafa Boztas, who was in the Al Noor mosque during Friday's shootings and was shot in the leg.
''We've had more important things to do.''
Southern Institute of Technology chief executive Penny Simmonds said she had not heard anything officially, but believed it was happening ''in recognition of the disruption caused by the Christchurch tragedy last week''.
