Please ensure that + present perfect

I just found a sentence like this "please ensure that you have returned to your seat prior to ~~". in some novel.

And this was an announcement in a train that just came to a stop at the station. (the train would resume in a few minutes)

What I want to know is, does it still have a same meaning even if I change the phrase like this ?

"please ensure that you will have returned to your seat prior to ~~"