There have been several changes regarding the use of the slots that were just acquired but DL is adding service to a number of Florida markets in the next few months.
There will most certainly be add'l markets where they will drop flights but there will also be those where they will stick it out w/ very low load factors and may add additional flights w/ perhaps equally low loads for strategic reasons.
DL made a comment about pulling about 8% of NYC local passengers that previously used EWR over to LGA... not sure of the complete context but DL has a larger footprint at LGA than any carrier has ever had and it will take time to sort it all out and see what works.
DL also is running a hub at JFK which works differently in some respects but does the same thing in other respects.
And, yes, there is a fair amount of slack in slot utilization requirements - including, I believe - most flights do not need to be flown on Saturday in order to meet slot usage requirements.