Lighten up. A little sarcasm never hurt anyone. I’m sure BK can handle it.

To your point. It does show up in the report before you submit it because I just did it and checked before I responded to BlackKnight. My Feb report is not yet submitted. I associated a seat selection fee with a revenue flight and clicked “submit”, entering that expense into my Feb report.
When I then click “review/submit” in the list of reports to look at Feb and scroll to that expense I incorrectly entered, it has the exact red message that BlackKnight said he had in his report. That message is there prior to submitting the report. I click “remove” on the expense, correct and re-submit it into my report. The message goes away.
The message also shows up if I associate the fee with the last revenue leg of a trip into MEM (like one would do with a ticket purchased to get home).
The only thing I can’t verify is what would happen if I submitted the report that way, because I can’t undo that.
My guess is the system does let you submit it that way because that message is showing any time the seat selection fee is associated with any portion of a trip that’s not specifically a deadhead. Why would it come up for me before I submit and no one else?
Regardless, it’s a system glitch that should be fixed because obviously not all legit seat selection fees can be associated with an actual deadhead leg. Some pilots may not even have a deadhead on their trip at all and still could submit a valid SS fee for their flight home.
Another FYI - it appears that the system auto-denies the fee if it’s associated with a segment of the trip that is outside of 3 days from the date of the seat selection fee, even if that trip segment is a deadhead. In that case, it automatically changes the expense to unauthorized before you even submit it into your report. It still lets you enter it into the report and once it’s there, there is no red message. It just shows up in a specific “unauthorized” section at the bottom of the report.