UPDATE: One of the aspects of this issue was that my render distance was set above the recommended value. Some time ago I reset the render distance to the recommended value of 50 chunks and since then this world and another which was exhibiting this issue have worked for me. I have not seen the issue reappear on any other worlds ever since resetting the render distance

ORIGINAL DESCRIPTION:

Two worlds created with Preview 1.20.60.24 eventually became unloadable due to a corruption issue which causes the worlds to fail to load with a "Server sent broken packet message." The first world failed after saving it for the evening and trying to load it the next day. The second world failed when returning from the Nether after approximately 28 hours of play. Both worlds had multiple explored level 4 maps if that is helpful to reproduce the issue.

Although this has the same message as MCPE-176333, this is different since it is on a single-player game occurring with the internal Bedrock game server and happens during world load or dimension change. No other players are present.

This has not been happening to my worlds on 1.20.51, which I was playing up until the 1.20.60-24 release last week.

A link to the second world is provided for examination (164MB download):
Preview 12060-24-B.mcworld  (link to avoid lack of https issue: http://xadyn.com/Preview%2012060-24-B.mcworld )

Steps to Reproduce:

• Create a new survival world in Preview 1.20.24-60, set simulation distance to 12 chunks and enable all three experiments.
• Play the world for a day or two, exploring vast areas of the world. Save and load several times.

Expected Results:

The world should continue to load no matter how many saves or dimension changes occur,

Observed Results:

The world eventually becomes corrupted and no longer loads.