I suspect, but don't know for certain, that the Felon isn't interested in the "pipeline". Based on everything we know about him, and I think he wants to skip the hearings and go straight to loading them on C130s.

I'm sure that's right - or rather, I doubt he's really aware of (or focused on) the fact that these folks are entitled to a hearing prior to deportation.

But they are, and the government wants an enforceable order of removal. So regardless of whether Trump is interested in the pipeline, they still have to go through it. Which makes means that if you go out an arrest these people, rather than just letting them live their lives and check in while their cases are pending, then you have to have someplace to put them. And if you don't massive expand the immigration courts, you'll need to keep them in that place for quite a long time, until their case can get heard.

All that costs money that the Administration doesn't have yet. If the Senate approach to reconciliation gets traction, they might have it soon - if not, then it could be well into the year before an appropriation gets to them. Which is why they're trying to kludge together an alternative to just expanding the system. But that's hard to do effectively.