i read through the faqs and the e500 post. it seems like that post is for people who already know as it gives tips and tricks. my question is much more of a noob question

if i am premier exec, is there any way to get an upgrade without using any upgrade item i.e. 500 miler etc... is it possible to get an upgrade just by asking if there is space available in first? so like, would they take off with space available in first if there is a 1p sitting in coach?

also, when can i board on united if im in coach and 1p? when they call out first class, or when they say zone 1?

also, can i request an upgrade via 500 miler online before my window and just have it clear within the window, or do i actually have to wait until i am within the window, then request the upgrade? i.e., can i request a 500 miler upgrade 2 weeks in advance?

what causes a 500 miler upgrade to have to clear at the airport instead of within the actual upgrade window. ie. shouldnt all premier exec upgrades clear online 48 hrs before flight (when the 2ps get a chance)?

thanks, sorry the one question turned into several