If I ask a flight attendant
いつ、とうちゃくしますか?
versus
とうちゃくは何時ですか?
Is there any difference in nuance if I want to know how much time is left until we land? Meaning, I want to know how many hours and minutes we are airborne, not at what local time we are expected to land (figuring out the aircraft's timezone while in the air is not always easy).
I noticed that there already is a similar, more general question posted here, but mine is more specific.