When an instance runs and there are existing mob factories, then all those factories will start generating fake spawns to try to learn the loot drops of that particular mob/looting level.

Although these are configured to be be every 40 ticks by default, it means that all the factories will be trying to learn at the same time, possibly within a few ticks of each other.

It might be wise to have the first learn event be offset by a random value to try and spread this initial learning load out.

Simplest way to do this is to set the learn ticks on each te to be the config value + random(0->X). That should offset them.