That's really not the case. Traditionally, committees that are due to end at 5:30 end at 5:30 by default. I don't know where this new idea comes from.
We all have calendars. We can agree by unanimous consent to extend, but it's not by default that it goes two hours. If the government decides to have votes, we have votes, and committee time ends at 5:30.
I have 20 constituents who I'm having dinner with at 5:30. I'm going to be late, and I need to be there, but that's not my fault.
The committee time is 5:30. It's 5:30 right now.