I'd rather be open jamming our stack and I hate reshoving a hand so weak as we seldom dominate anything but are occasionally crushed by higher Ax hand. 

Agree, this hand would be so much more worth it if we had some FE, which we don't when UTG+1 already moved in. A4s is a pretty hand, but I don't think it's good enough in this spot. Would probably reshove something like A8s+.

I like it, you are pretty short and can't get many more better chances to shove /any aXs is strong here/. FE with hand like that is always nice, but it is also nice when you reshove here and everyone else folds /which is the common case imo/ and you are not playing for your tournament life.

I think you need to get allin here. A few things I like to think about in these situations. I ask myself, what's the worst hand I think he's shoving here? Once we know that, they we know his range! We know he's shoving AA here, so the top of his range is easy to figure out. I see many players shoving as wide as 56s here. If he's one of them, or anywhere near that, then consider how many hands he has in his range that we're ahead of. It is a fair bit more than hands that beat us. Another thing to consider is the price that the pot is giving us. Because his shove is for such a small amount of BBs, the importance and value of the price the pot is giving us becomes even more important. Put another way, the amount that is in the pot from the blinds and antes is a bigger percentage of the total pot when he shoves for 3bb than when he shoves for say 10bb. 

Imo there are too people behind to reshove here... maybe if we were in BTN and the others fold till us?

Agree with Gio/Nick.  The combined double all-in's may turn away slightly stronger hands behind us from reshoving who would have otherwise while we are not risking our tournament life and have a potentially very profitable uptick spot for our stack against a wide range.  Of course hands like JJ aren't turning back - but we're late enough in this spot to shove profitably. +3BB in UTG1 is going to have a very wide range which we do well against.