To find out what stairs you can currently challenge someone in, first go to the Main Stairs Page, then click on "Show your stairs only" link. The ones in BOLD are ones you can make a challenge in. .
srnity: No..you dont need to "ask", but if you challenge an opponent who has "no autopass" in settings than you cant use it either. So in fact its your opponent who decides if your settings are in use or not....fair?...ask Fencer :)
playBunny: A top dice roller (no name!) said to me not long ago "To play 17-1800 rated players is to steal candy from kids"..then i cant understand the fear for losing BKR...can you?
My sympathies to the topplayers (top dice rollers in backgammon) who must play lower rated players. If they should lose (awful thought!!) they could lose some of their so well deserved BKR. If i was a top dice roller i should absolutely restrict myself to not playing any stairs at all