Yes. I found that out a few years ago, when I was starting to fill out the Delta application. I tried my original login and it worked. It immediately said that I had to pay the fee to do anything at all, including see what was in my profile. So, I paid the fee and Eagle sent me an email, asking me to update my application because it looked like old info. Turns out, my old profile was not same as the profile I was using to apply to Delta, so I basically wasted $60 and Eagle's app system's time. I had filled out that profile for Eagle in like '06 and this was about '08.
Airline apps is actually pretty convenient IF you pay the fee.