They're already teasing about the next pack (The gurus are hinting heavily today)

"alanmichael1;c-18080992" wrote:
Honestly I think they should fix their recent packs first.

They work on multiple things at the same time. Obviously they are working on fixing packs as well. And these few tweets won't really consume that much of their time, on top of that it's weekend so there is a high chance they are tweeting in their free time, and free time means they are currently not working and it's not paid.