The short-term extension of federal government funding expires on February 18th, which is less than four weeks away. Unless House and Senate appropriations leaders very quickly agree on a topline for spending, and the split between defense and non-defense spending, there won’t be time to agree on every programmatic funding level, which means Congress would need to extend current funding for a third time to keep the government open while negotiations continue.
Regarding Build Back Better and Reconciliation, the President and some congressional leaders have spoken publicly about breaking out some parts of the proposed bill to consider them as standalone bills. The budget resolution’s reconciliation protection could be used to do a much smaller bill that would require only 50 votes to pass in the Senate, or bills could be proposed under regular procedures— but those would require 60 votes to pass the Senate, a bar that is likely to be hard to reach on most provisions.