They’ll be fine. You can get a well-managed team promoted out of L1 with a budget that their owners could comfortably afford to bankroll for years to come, at which point the commercial and sponsorship deals go through the roof.
These fellas can more than afford the budgets that the likes of Plymouth and half of the clubs in the playoff places have, as well as what Wycombe had the other year, what Blackpool had the other year, what Rotherham have every time they go up, what Barnsley have every time they go up, what Millwall had, what Luton had etc etc.