You're going to have 2 sources for available housing once the demo timer is reactivated since it's occurring at the same time as the data center reorganization.

For the first 2 weeks, you're going to see many houses become available due to players transferring to other worlds during the free transfer period. Few of the house openings during this period are likely to be due to demolition.

Once the free transfer period ends, you'll see a trickle of house becoming available via demolition for about 4 weeks. Once 45 days has passed since the timer was reactivated, you'll see a flood of houses open up as those would be houses owned by players who quit after the timer was suspended.