Block(s) placed do not appear right away, but are physically there.
The issue is reproduced the longer you stay in between the ocean and a coral reef while playing single player (non-realm) survival mode.
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[Mojang] Mega_Spud (Jay)
migrated
Yes i even try building in peacful only with no mobs, no kelp stocks near, and an ocean wood roof near me to darken ocean and avoid aquatic life spawning. All this to avoid any unnecessary ticks but i still get the ticks updating late.
[Mojang] Mega_Spud (Jay)
Thank you for your report!
We're actually already tracking this issue at MCPE-34910, so we will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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I've labelled these bugs 'switch-lag', as it may be the same underlying issue. Have you tried toggling the difficulty to clear out any groups of mobs that might be causing the lag issues?