We often hear from badidol:
"We won't remove the black market, but we will solve the banking problem. But for now, we're just talking and doing nothing"
I think if you've left vacation and want to go back immediately, you're probably using your account as a bank.
Therefore, if you make vacation mode cooldown at least one day, there won't be any banks left.
They'll either be killed by players during that day or they'll run away due to lack of gold.
I really hope the developers finally solve this problem.