"similar" here takes about twice the time it did before (ignoring the +2hours) -
i don't keep track on steams time only the time that passes on the RL clock ...

this user had good and plausible theory for it, that might be the cause:

"Steam doesn't track ingame time correctly anymore (few weeks now) and that affects card drops. Ingame time only increases on 0.5 hrs intervals instead of 0.1 hrs."

http://www.steamgifts.com/discussion/syQ1l/whats-wrong-with-farming-cards-currently-takes-too-darn-long#hR1iBGZ

http://psteamcommunity.yuanyoumao.com/groups/idlemastery/discussions/0/490125737469153259/

^ else i'd have no idea or would simply assume its the games or the drop rate changed