[2021] My heirloom shards did not stack

@GrammyPatty Looking into this, there's a misunderstanding here. There isn't a chance of getting shards from Event packs.

Your earned shards were from finishing the event. You then opened a standard Apex Pack straight away afterwards, not an Event pack.
It sounds like this final Apex pack was mistaken for an Event pack. 

I hope this clears things up. 

Oh and @ThickGrape I have seen some (very rare) cases of accounts having over 150 shards, so it is possible.