5/10 plo weird spot

[T-God]

I'm SB with 3[img]/images/graemlins/diamond.gif[/img]5[img]/images/graemlins/diamond.gif[/img]4[img]/images/graemlins/spade.gif[/img]6[img]/images/graemlins/spade.gif[/img]

UTG ($500) minraises to 20
Button (900) calls
I pot it to 90 ( I cover), BB (400) calls, others call.

Flop is K[img]/images/graemlins/diamond.gif[/img]2[img]/images/graemlins/diamond.gif[/img]Q[img]/images/graemlins/spade.gif[/img]

I check (?), BB checks, UTG bets 40 into 350 (wtf), button calls.

I... call (?), BB calls.

Turn comes J [img]/images/graemlins/spade.gif[/img]

BB bets out 80 into 500, UTG disconnects and gets folded, Button pushes AI for 750-ish.

I fold.

This weird betting wasn't standard for this game from what I've seen so far and I don't have any good reads yet as I sat maybe 5 mins ago.