I guess I am terribly misunderstanding something. You said "If I select 175 I will reduce the 175 slots offered to the rest of the class by 1"... Well yes, that is the way seniority works.

What am I missing, and why would I end up going to the CRJ? I do understand CA CRJ is most junior, but I fail to understand what that has to do with the original question? Honestly, I only care about Envoy for the DFW base. I'm honestly only interested in my chance of getting DFW based, which the 175 seems best for. So, I guess, what are my chances of DEC being able to get awarded DEC as a new hire and also being able to hold DFW in that 175? Obviously there are no guarantees, but I'm wondering if that is a possibility.

Zero. Absolutely zero. The junior 175 pilot is in ORD with 21 months of seniority. You won’t be able to hold DFW 175 until you’ve been here around two years.

When I was hired, people who had accepted the DEC bonus were allowed to bid for a new hire status based on class seniority, including FO seats, the NCE seats were only "offered."

DEC 175 DFW will not happen under any circumstances, that is the most senior seat in the company.

The 175 seats are FO. If you qualify for a direct entry captain, your paperwork may read differently, but even if they ALLOW you to bid for the 175, as an FO, you will be displaced to Captain immediately, at the latest the next bid, which have been every three month, so before you finish training. As the most junior Captain in the company, you will be stuck with a CRJ, MAYBE a 145, in ORD because that is
all the most junior captain in the company can hold.

Yeah holding Dallas, as others have said will take time. It’s our most senior base.

This is actually a pretty good situation for new hires.
Assuming you're a cadet/lucky with 0 qualifying 121/91k/135 time, and get DFL out of training. 21 months later you might upgrade straight to DCL.

Wouldn't count on getting the 175 on upgrade after being on it as an FO. With the huge night/day difference between the rates that FOs on the 175 vs. the obsolete fleets are getting hours now choice upgrade slots are likely to be more contested, especially uncertain for people on the normal ~18 mo. upgrade path. I'm 12 months behind with essentially no flying, and so is everyone else hired around the same time into the WSCOD. The situation seems even worse on the CRJ side but may actually balance out w/ more flying on rsv.

Yeah, I was making the assumption that you couldn't fly 1000 hours in 21 months, even on the 175.

It would be easy in ORD tbh

Ok that's good info. How are the 175 lines in DFW?