When a priority stream becomes active and goes live, there are two possible behaviours that can be configured in Settings > Advanced Scheduling > Priority Streams:

Fade immediately: The currently playing track will fade out and stop immediately to get the priority stream on-air as quickly as possible. This ensures minimal delay but means the current track will be cut off mid-play.

Wait for current track to finish: PlayIt Live will wait for the currently playing track to complete before bringing the priority stream live. This provides a smoother listening experience as tracks aren't interrupted, but the remote stream will have to wait longer before their audio goes on-air.

When the priority stream ends and becomes inactive, playout behaviour depends on your Priority stream inactive behaviour setting. It will either return to its original playing state (resuming if it was playing before the stream went live) or automatically switch Automation ON to ensure playout always resumes.