Alternate Page displays as soon as I set the rule

So I’ve set my time zone and set the front page. When I add a rule for the alternate front page (I’ve set the time at 30 minutes from now- 13:00) and select the day of week (today). I’ve left “Stop at” empty but also tried with a 23:00 value.

When I save, the front page is immediately switched to the alternate.

What am I doing wrong?

Thanks for your help!