My server is a 1.12.2 map that I upgraded to 1.13, then 1.14, then 1.15, then finally 1.16 at the end (all today). I couldn't "convert chunks" because Aternos would auto-crash my server after 2500 chunks were converted, even though the speed is constant and not stopping, meaning that the chunk conversion was working fine. So, because I was not able to convert chunks, I just decided to go up version by version without converting chunks. However, every time I try to load new chunks onto the server, the chunks just don't load - it's just ghost blocks. And then, the tps randomly drops from 19.7 to 0.7 and never recovers and I time out. And the logs keep saying that there is a lot of lag going on (and things are behind by well over 10000 ms, sometimes even hitting 20000-40000 ms behind).
Btw, the map is a 700 mb map 1:4000 replica of the Earth.
So now, I'm stuck with a server that never works - ever. Chunks won't load, tps drops precipitously, and I time out within 5 minutes and am unable to reconnect to the server all of a sudden.
And the only plugins I have are a seasons plugin (which works for 1.15 but is tested to work for 1.16) and WorldEdit.
What do I do? I've looked through the forums and have found no useful answers to this at all.