Optimum Modpack

Added: 

Comforts(Forge) 

Updated: 

Ars Nouveau
Create
DeLogger
Extreme Reactors 2
Forge
Inventory Pets
Just Enough Items (JEI)
Just Another Void Dimension
MineColonies
Modular Routers
RandomPatches (Forge)
Refined Storage
Tetra

Also, You can update The Undergarden mod only before creating a world. If you created a world before updating, you will face a data pack issue which currently doesn't have a solution. If you accidentally updated Undergarden then you can downgrade it to 0.3.8 version to fix this issue.
If you created a world with 0.4.0 version of The Undergarden, you will need to update it each time the modpack updates.

There might be an issue where waypoints are not saved between updates. So, you might want to save the coordinates before updating or some other form of saving them like placing waystones to those places.