Gas door release

Just got back from a 3500 mile trip and noticed my gas door would not open right away about 20% of the time, a little screen would pop up with a timer line and then open after a 20-45 seconds. Anybody else seen this?

Made me nervous since I was out of town didn't want to have to rip it open to get gas.

 

Suspect it's a safety feature related to letting the tank depressurize. But it's just a guess. Clearly expected if they was a displayed countdown timer.