I am on premium and get 2 daily quests. Today i checked my number of shards and had 1. I then finished my two daily quests, worth 4 shards each. I then found all collectibles worth another 4 shards.
I now have 5 shards.
I noticed this yesterday although i did not keep track of number of shards as i did today. My guess is this is a new bug since the fix that happend and i have lost a good number of shards recently.