Unable to enter external Bedrock server after Minecraft 1.26.52.3 update

After updating Minecraft Bedrock to version 1.26.52.3, I am frequently unable to connect to my external Aternos Bedrock server.

Before the update, I could connect normally. After the update, I receive Kelp, NetherNet, or Door multiplayer connection errors. Sometimes I can enter the server, but I am then disconnected.

My other Minecraft multiplayer servers work normally.

Device: OPPO CPH1901
Android: 8.1.0
Minecraft: Bedrock 1.26.52.3
Server host: Aternos
Server software: Bedrock
Server version: 1.26.52.3

I have tested both Wi-Fi and mobile data. I also restarted the server, re-added the server, and used the current server address and port. My friend has also experienced similar NetherNet connection problems on the same server.

The Aternos server starts normally and its logs do not show an obvious crash.

Expected result:
I should be able to consistently connect to and remain connected to my external Aternos Bedrock server.

Actual result:
The connection frequently fails with Kelp/NetherNet/Door errors, or I get disconnected after joining.

The problem started immediately after updating Minecraft.