Why the difference? Legislative Management 101 states that you do not get to the see the redistricting maps until you have voted on the budget. Scheduling the budget vote before the release of redistricting maps keeps you focused on the leadership's budget priorities. You always wonder if you get crosswise with the leadership on the budget, will it have an impact on your new district?
Assuming that the Senate passes a budget this week, expect to see the Senate lines next week.