Bug Description

I'm currently running the latest version of SevTech: Ages (version 3.1.5) with all the default mods enabled, except for three mods: Better Foliage, Fancy Block Particles, and Smooth Font (as these are a little taxing on performance).

Aside from the default mods in this pack, I had only added in OptiFine_1.12.2_HD_U_F5 (clientside), which greatly helps with performance.

Now, after having been flawlessly running a SevTech: Ages server for almost over three weeks now and reaching the 5th Age, upon logging in a few days ago, I noticed some corruptions in the world. After investigating a bit, I noticed basically all of the block ID's from the mod PrimalCore had been switched around (essentially they were remapped).

https://imgur.com/a/347tYOj

As seen in the picture here, what is supposed to be Terra Clay has converted to Ovis Atre Wool. Also seen to the left, Wet Mud converted into Inaris Carpet, and in the background, Rushes converted into Jack o'Lanterns.

After looking at the ID mappings for a bit, I noticed it was the third digit that shifted down by one. For example:

Wet Mud ---> Inaris Carpet (ID:2642 --->ID:2632)
Ortho Stone ---> Oak Drying Rack (ID:2595 --> ID:2585)

I'm not sure how this happened and I don't see a good reason as to why it should have happened, but it seems to have happened sometime when the server was empty during a constant uptime period of around 5 days. I have also been doing proper server shutdown procedures (typing stop to close it).

While this is obviously a corruption, are there any suggestions on how it might be fixed?

Backups are out of the question because AromaBackup was not personally configured and so it only had backups ranging from 1-4 hours ago (my fault).

This corruption also takes place in the End and Nether where there are a decent amount of blocks from PrimalCore in the environment. I think the easiest fixes for those dimensions would be to just delete the DIM1 and DIM-1 folders in the save file to reset those dimensions. But are there any suggestions on how this might be fixed for the Overworld?

Also, just to be clear, this corruption happened in chunks that had been previously generated (no corruption found in discovering new chunks).

One thing I tried was using the /worldutils blockreplacepairs command from the World Utils (https://www.curseforge.com/minecraft/mc-mods/world-utils) mod and it works somewhat, but it doesn't seem to have to have a very long range, even though it says it should replace all blocks throughout all previously unloaded generated regions.

Did this behavior use to work in the previous version?

I can't say, I have only been playing on version 3.1.5.

Steps to Reproduce (for bugs)

N/A

Logs

N/A

Client Information

• Modpack Version: SevTech: Ages 3.1.5
• Java Version: build 1.8.0_261-b12
• Launcher Used: ATLauncher
• Memory Allocated: 5 GB
• Server/LAN/Single Player: Server
• Optifine Installed: OptiFine_1.12.2_HD_U_F5
• Shaders Enabled: No

World Information

• Modpack Version world created in: SevTech: Ages 3.1.5
• Additional Content Installed: No Addition Content

Server Information

• Java Version: Version 8 Update 261
• Operating System: Windows 10 x64
• Hoster/Hosting Solution: Own Server (from personal pc)
• Sponge (Non-Vanilla Forge) Server: