http://weaktight.com/6725599

This hand happened yesterday in the FPS 300€ 6max on pokerstars.fr.

CO has been playing straighforward/tight thus far, no special reads. I 3bet pre bc BB has been pretty squeeze happy, active and overall seems to be decent (26/21/13). 

History with BB: 

1. I 3bet from CO vs. an UTG-raise, he 4bets OTB, I fold.

2. He opens UTG, i defend 33 in the BB. c/c on a J73r board. turn 6 is checked through, river blank is checked through. he shows up with A6s. 

What do you think is a good general strategy here (being cold 4bet oop by an aggro oppenent, with stack-sizes and bet-sizing of this hand)?

Maybe shove AJo, ATs+,44+, fold the rest? Would you ever flat (with hands like QJs)? I don't think 5betting is an option here regarding stack-sizes.