I'm sure you've heard this before but being on reserve versus being a line holder is almost like working for two different companies.

Reserve pairing aren't subject to duty or premium guarantees. Line holders typically would only wind up in a situation like that if there were a maintenance problem at an outstation or bad weather delays. Myself, I haven't been delayed more than an hour or so in years.

Just another one of the reasons why hundreds of FOs that could upgrade choose not to. -- or why the "lifers" choose not to move on and start over at the bottom.