We tried to fight the wither in the end and left when it was about half health. when ever we reload the end after defeating it, it will respawn. It always respawns at half health in the same chunk. We have tried leaving and re entering the end and have killed it 5 times with no success at stopping the glitch.
Thank you for your report!
We're actually already tracking this issue at MCPE-62332, so I will resolve and link this ticket as a duplicate.
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