Unknown man and woman

The picture is of a man and woman sitting in a hall.

They are obviously preparing for a celebration of something.

There are flags - one has a harp on it.

There are also pictures on the wall.

This photo may be from New Zealand or Manchester, UK or Middlesex.

Please is anyone able to date it, what are they commemorating? say where it may be.

It was found in a great aunt's box after she died but no-one has any idea of who the people are or what they may be celebrating.