The time in a lawsuit when the complaining party has stated their claim and the other side has responded with a denial and the matter is ready to be tried.
now in consideration or under discussion; "regarding the matter in hand"
Parties to a suit are at issue when they reach a point in the documents where the parties disagree. Basically, facts are alleged to exist by one side and are denied by the other.
Point in a lawsuit when complaining party has stated claim and other side has responded with a denial. Contested points are said to be "at issue."
Pleadings are answered and ready for discovery and trial.