Guild Wars 2

Im lvl 34, can I do lvl 40 and get lvl 40 daily chest?

Or would this still count as my daily 30-39 tier chest?

You get the rewards for the lower one your level, or the current difficulty your playing.
Since 34 < 40 you’ll get rewards for lv 34 in 30-38, even if you succeed in lv 40.

Your level is 34, so if you do lvl 40 fractal you get lvl 34 loot, and then move up to lvl 35.

I understand that, but im talking about the daily tier chest, at present I can do one daily for 2-8, 10-18, 20-28, 30-38.

Can I now join a 40 and get that tier chest too?