Both sides face a tight turnaround to reach a full agreement before the Premier League transfer window slams shut on Tuesday, September 1, at 23:00 BST. Forest are eager to finalise their summer business after already completing moves for Steven Banda, Ousmane Diomande, and Liam Delap alongside Schlager. Sorting out Armstrong's club future before the deadline will provide clarity on his first-team development ahead of the upcoming autumn international break.