Is there any reason at all that you would not be hired as a cfi immdiately after your training? Granted you are successful in your training and testing?
No, there isn’t. As long as you don’t fail more than two checkrides (which you shouldn’t anyways), then you will be guaranteed a CFI position with ATP.
Just keep in mind that there seems to be a big delay with everyone that has recently gone off to CFI school. Everyone that I know that has been there in the last several months gets through the ground quickly, but gets delayed significantly when it comes time to flight time. It sounds like it might be a DPE availability issue because people are getting sent all across the country to get their CFI initials done. So, yes, you should be able to get in immediately, but the training might be a bit delayed.
Can I ask where the people you know did there training?
Of course, everyone from my location recently has gone to CFI school at ATP Atlanta (KLZU). My understanding is CFI school delays are nationwide, so it really doesn’t matter where you end up.
Keep in mind ALL CFI instruction for ATP is done in ATL, JAX or LAS and yes there is a backlog due to the DPE shortage.