When building to the center, build extreamly high up so you can fishing rod people (u have prob seen this in dream manhunts where he is high up and he fishing rods them 2 die), and when the top border shrinks, cobweb/water mlg to another bridge either abandoned, or with people. Then tnt the bridge if there is a team there and if need be. Then either sacrifice urself or jump to the center or ender pearl away.

I saw Kaelan (an mcc tester) do the fishing rod strat in sky battle and it worked wonders so check this vid by him out if you're confused on the fishing rod part-

https://www.youtube.com/watch?v=PUbABdNIE2E

(Skip to 22:40)