I have pretty much the same answers as Adam. With a Latitude FP, you're booking into Y, so you'd have the same availability as anyone buying an economy class ticket.

I don't think there are fees for no-showing on limited-credit passes. You just forfeit the credit.

You can book flights up to 2 hours before departure. I think TECHNICALLY the terms say 2 hours for changing/canceling, but I've successfully done both MUCH closer to departure.

I find they tend to deliver good value if you you're booking flights within a month of departure and you can definitely use all the credits.

I'm probably going to buy another transcon Y pass, because it's about the same price per segment as a P fare with a 15% code, but it lets me book last minute and change my flights (I had a... "discussion" with family over our Thanksgiving plans, as they wanted to have dinner on a different day after I bought P fares per a June discussion with them).

In the past month I've purchased 3 Y passes, and booked about half the credits with full intention of flying all of them by the end of January.

FPs are amazing.