First connection to the server pretty much always works, but any subsequent connections fail with a "Timed Out" status.

Forge version: 36.2.26
KryptonReforged: kryptonreforged-mc1.16.5_v1.0.0.jar
server log:
latest.log

client log:
latest.log

The only mod I had enabled was KryptonReforged.

Getting the exact same issue, thought it was another mod at first but tracked it down to this one.

The way I found out about it was because I have the Discord Integration mod installed and set it to kick me if I don't have my Minecraft account linked to my Discord (in my server)

I connected once fine and was kicked with the prompt.
Then, after linking, I was stuck in the "Connecting to server..." screen for around 5 minutes.

Removed the Discord Integration mod because I thought it was causing the issues and tried the same:
Connected once perfectly fine to my server, disconnected, and when I tried connecting again it ran into the "Connecting to server..." timeout again.

Can also confirm happening here as well. First login is always successful, 2nd time "Connecting to server..." forever.

Can confirm this issue aswell.

Yes, can also confirm this. Running a 1.18.2 and it appears that similar issue occurs. Even the "Pinging server" has some issues.

can also confirm this. 1.16. on a custom pack.