The word preferred gives them flexibility, there are times they will take people without it and times they won't, historically about 90% of those selected have the educational background that includes Calc and Physics They seem to overlook that for those that are in a IWC rate and to me that makes sense.
If you are over 10 years you would be a long shot as that is outside the waiverable requirements. There are 2 things to remember the first is that NRC should decline to waiver you, but they now don't like to be the bad guy so they will often approve the waiver so you can go to board to then let the board say no, the other is that they limit selection numbers of those with waivers which means if you get a "no" did you get a "no" because they didn't consider the waiver or because you weren't one of the "limited numbers".
For IP DCO, they preferred Masters and Calc I etc .. I had neither and was selected. I guess I'm part of the magic 10%. But, my gouge always remains the same .. your chance is actually 0% if you don't try. Don't see how that point can be argued whatsoever.
Motivational statement, past work history, interviews matter a lot for the DCO boards.
In ref to Rhodes .. they said 1820, so assuming AC? If AC, then High GPA and OAR will matter more than Calc I/II and Physics.
In IPBC ... I had plenty of history majors and guys who straight up would struggle to replace a keyboard on a PC.
What will be interesting to see is what SRBs eventually roll out for IWC designators (including the new cyber one). I mean how else are you going to stop guys like me from running off to Microsoft? or even PEO-D where I can work in pajamas from home all day tinkering with new platforms/products.