The lame-duck session is the session that immediately follows an election (usually just a few days after election day). It lasts until that session ends with the adjournment of that Congress and the installation of the "new" Congress on the first Monday of January.
Typically, the lame-duck session last from the first week in November to the time that the Congress breaks for Christmas. So, we're talking roughly 6-8 weeks.
Ok...so the idea is they know they’re on the way out so anything can happen in those couple months. Yikes! No wonder you have concerns. What will they have lined up to push threw on their way out the door!