The project team is ahead of schedule and beginning lo gold-plate the feature included in...

Since the team has extra lime, notify the product owner and secure approval for the extra work on this feature.

Encourage the team to document the improvement and prioritize it for the upcoming iteration, instead of building it now.

Instruct the Scrum Master to have the team use the extra time to complete the extra feature work in the current iteration.

Notify the product owner and have the product owner verify the backlog priority, then encourage team to continue working on the backlog.