Reload bonus (at UB) question

[LoyalFrush]

UB is offering the 20% reload bonus but I can't find any details on the restrictions regarding the promo. I assume I can't deposit $500 to get the max 100 bonus dollars and then 5 minutes later withdraw the $500 back out. Do I have to keep the money deposited until I clear the bonus money or is there a specific length of time that I can't withdraw money?

Thanks for the clarification.