There seems to be something weird going on recently with how the warehouse determines free space. I just got a notice in my reports that one of my pets had found an item during a quest, but had dropped it due to me having no space. My item limit reads 96/100, and none of my items are at max quantity except Pure Snow. If Pure Snow can be obtained through quests, I suppose that's the answer, otherwise I don't know what's going on.

Also, a week or so ago, I tried to pick up a Hibernating Egg on the Tundra, but was told I didn't have space. While my item limit was at 100/100, I already had Hibernating Eggs in my warehouse, so I should have been able to pick it up.

Finally, it seems that my item limit has been fluctuating slightly without my having gained or lost any items, sometimes at 100/100 and sometimes at 97/100 or 98/100. I'm not 100% sure about this one, since I regularly have to destroy extra schemes to make space and forget that I did it, but I thought I'd add it anyway.

Whether this is all due to my own confusion or an actual issue I can't say for certain, but I'd appreciate having it sorted out.

We just thoroughly tested item collecting and limits and found only one issue that concerned collecting food from Polar Salmon over the limit. This bug has been fixed. Everything else works as expected.

Pure Snow is a regular item, so you're correct that your pets can bring it from quests.

Concerning fluctuating item quantity, usually this happens due to normal game events, like food being used or added (Tundra food adds 3 types of food at once), items being sold or exchanged on the auction or on islands etc. 

Hmm. Okay, thank you for investigating for me.