Space 220 restaurant reservations have consistently been available for 60 days out.
Until recently and for an unknown reason, Space 220 lounge reservations stopped at January 31. Then, yesterday (January 8) at about 5 AM, Disney made the lounge available all at once for February and into March, up to 60 days out.
One possibility is that they were considering ending reservations at the Space 220 lounge.
Another is that they were analyzing data from previous bookings to determine how long people were staying in the lounge. This analysis was then used to set a new booking schedule for the lounge. Remember, Space 220 is new while reservations at lounge are even newer. Although data from Oga's (another Disney bar with reservations) might have helped, those setting up the Space 220 lounge reservation schedule had to give it their best guess until they had data that was specific to Space 220.
Either of the above would have taken time to make a decision. Presumably, this had to wait for the first full week of January when everyone was back in the office.