FNLT Constraint - How does this constraint affect projected start dates?

Hi All, My teams are having some challenges with shifting projected dates because our projects are almost always on very tight timelines and there are so many factors that can impact those dates. I'm looking at using the "Finish No Later Than" constraint. My question is this, if a predecessor task is completed early, will the projected start date move earlier on a task with the FNLT constraint? Thanks!