Sorry if this is the wrong place to say this but I just saw this daily tip at the top of the forums. It says:
“Did you know?
Rarity of a particular pet is determined by how many of those pets are owned by active accounts!
You might see your uncommon pet suddenly change to rare or vice versa, and this is normal. Changes happen all the time as the pets get traded and players come and go.”
This should be changed to reflect the rarity update to not confuse newbies. Something like “You might see your uncommon pet suddenly change to very uncommon or vice versa, and this is normal.” Or “You might see your extremely uncommon pet suddenly change to rare or vice versa, and this is normal.”