Here is my somewhat recent experience with the next steps as far as Exelon goes,
Received an offer around 9/2013, Fire brigade physical and clearances were given out about a month prior to starting. I started beginning of February where after a week or so we (my EO class of 10) rolled into GFES training. After GFES, we went to Fire Brigade training for a little over a week. Systems training was after that where, you guessed it, we learned about all of the plant's systems... So from my start of Feb until Aug we were in classroom training for the most part with weekly exams. In August we had an OJT portion of training where we went on shift with our crews to learn specific tasks and get more familiar with the plant. In January, most of us were qualified EOs. So about a year in total from the start date, did we become fully functional EO/NLOs.
If you're still looking Clinton Power Station is looking to hire another new EO class in January I believe. Job posting is on Indeed. Good luck