A few questions - Leesa Oasis Chill Hybrid

Hey everyone, I have a few questions that I'd love to have sorted before ordering this mattress from Costco. I'll be ordering the King size.

First, how long does the off-gassing last? My wife is 18 weeks pregnant and a cat and I don't want either of them getting sick from the new mattress's smell. I'm hoping to time the order so I can keep it in another room before we need it in our bedroom (more on that below).

Second, we don't really have great options for storing the mattress during the off-gassing period. With that said, all options lead to me having to cram this mattress down a small-ish flight of stairs. How much can I bend this before it's too much to make sure it fits. As mentioned, I'm ordering a King size.

Lastly, my wife likes a firmer mattress, I like it more cushiony, and we both sleep hot. Am I making the right choice with this mattress? Looking for personal experience. I'm less worried about me, more so want to make sure my wife sleeps well, especially while pregnant.

Thank you!!