I doubt if they will see this kind of opportunity again in the premier league and the reason why they even see this opportunity was because the big teams where having a tough time that is why they entered top 3 and then what happened when those big teams wake just a little, they displaced Nothingham forest from the position just imagine they could not even finish at top 5 or 6 at least that is to show that there strength have not gotten to that, they are very small team when it comes to premier league and if time is not taken they will be struggling with relegation next season, they have the golden opportunity to see the champions league after so many years of not been there but they couldn't make the opportunity count for them.
Yeah, Nottingham doing this good, was unexpected, but not like they won the league. Leicester literally won the league, and still managed to relegate, so it's clear that if you are not a big club, then you are simply just not a big club, even if you have one or two good seasons, that's not enough.
Nottingham may not have enough fans to make more money maybe, or maybe they do not make enough income, whatever the reason, eventually it is not sustainable for them to do great back to back. I remember when Leicester won, they sold many of their players for a ton of money, so we assumed they would get rich and get good players, but instead they got worse and sucked and went back to Championship level, so that means Nottingham could be terrible next year yet again.