Soleil x Olivia

Do other people's Summoner Supported heroes maintain their stat boost during when I fight against them in Arena? Or is the +5 HP +2 Atk/Spd/Def/Res only applied during when you, personally, use them in your own game?

How is Ally Support ranks attained? I heard somewhere that Summoner Support ranks is gained from just having your hero survive ~200(?) battles that have at least 1 lvl 35 or higher enemy. I don't know if Ally Supports is the same though. Do I just have to have my 2 heroes in the same battle, and survive, that has lvl 35 or higher enemies?