There isn't a big difference in money between L2 and L1, a lot would drive and on whether crowds would increase, but I guess somewhere between £500k-£1m, thats then counterbalanced by having to pay L1 wages. Only the premier league brings financial rewards, and that's only if you refrain from splashing too much cash, and keeping the wage bill in check. With the new TV deal in the prem, it won't take long for players wages to continue to spiral.
As for having a punt now, you probably wouldn't cover the money by promotion anyway, as not only would it be transfer fees, etc, you're likely gonna have to increase the wage bill, with not only imapcts on this season, but also next season as they get promotion bonuses and pay increases, and that's before you refresh the squad.
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