She said she shared in the disappointment everyone was feeling.
"I know this is a further disappointment at the end of a year that has been more difficult than most," Professor Hayne said.
"In the wake of Covid-19, our students have overcome huge obstacles to stay on track and complete their degrees this year.
"Moreover, many of our students and their whānau have made significant sacrifices to travel to Dunedin so they could be a part of these very special celebrations."
She was confident graduands would find alternative ways to celebrate.
All associated graduation events planned to take place on campus were able to continue. Graduands would still be able to pick up their certificates and details about this would be sent directly to graduands.
Hayne said despite last week's graduation postponements, graduates had continued to celebrate their achievements, with large numbers on campus last week and on Saturday.
"I have seen many, many examples of the true Otago spirit as people took the opportunity to celebrate, marking their achievements in their own very personal ways.
"They have demonstrated these characteristics throughout this year and their response to the graduation postponements is just another example of how truly remarkable they are."
For graduands who chose not to come to Dunedin this week, or who wished to take part in a full ceremony at a later time, the university was planning opportunities for this in 2021.
Hayne paid tribute to the police who continued to investigate the security threat.
"Police continue to take this threat very seriously and we are grateful for their support and expert guidance."
The specific and detailed threat against University of Otago graduation ceremonies first forced an eleventh-hour abandonment of last Wednesday's official proceedings for students.
Since then, hundreds of students have made do with informal celebrations only as graduation ceremonies have been successively called off.
