As shambolic as they are at the moment, and as toxic as the club is right now, it would take something special for them to struggle again next year in League One.
Their wage budget as a percentage of turnover permitted by FFP, even with half of it eaten up by the likes of Cattermole/Rodwell hanging around, will still leave them with 5 or 6 times the budget of clubs down there. So long as they're proactive they could hoover up all the best players in that division as the vast majority move around on free transfers.