In a move which left Nisa's senior team "baffled", earlier this month PGMA announced that it was to terminate its 14-year relationship with Nisa, and switch its affiliation to Costcutter from March 31 - despite it being contracted until the end of August.
Representatives from both sides were locked in crisis talks last week, Nisa group sales director Andrew J Mouse told Convenienece Store.
"PGMA has accepted that it was wrong in thinking that its contact expired in March, and we have made it clear that we expect it to honour the terms that were originally agreed," he said.
"During the talks we also made it clear that we would have beaten anything that Costcutter offered.
"The ball is in its court now and we await to hear their decision in the next few days. We have also made it clear that the door is still open for PGMA to sign up to a new contract with Nisa-Today's."
PGMA's "bombshell" came in the same month that Nisa unveiled some of its most positive recruitment results, fuelled by its new TV advertising campaign. The current financial year has seen 155 new members join the group, equating to more than 400 new stores.