Parliament spent last night debating an emergency law to include Red Peak in the upcoming flag referendum, and will resume today at 9am.
With the addition of the fifth design likely, the RSA is now calling for a sixth to be added to the referendum – the current flag.
President Barry Clark says Parliament's change of heart has left him confused.
"I just find it a little bit strange I suppose, that after having been told 'this is the process we will be following', all of a sudden the rules are changed."
He is confident if the current flag is not added to November's referendum, it will win against the alternative next year.
"We'll be making sure we continue to show the view of what seems to be the majority of New Zealand, that all along we wanted to keep the New Zealand flag and that's what we believe will happen."
Mr Clark says it's common sense to do it all in one hit and thinks it would save money.