A bounty campaign just like other campaigns will sure need to have certain regulations or rule before starting the campaign they surely have the rights to change the amount needed for their payments because the value of Cryptocurrency is not stable and it will sure base on the exchange ICO was base in, For some valid reason bounty hunters will need to manage their time if they are joining a campaign and certain ICO will need to raise their funds by starting a Crowd sale well if the management can not handle the expenses needed because it will sure need billions of funds to start your own coin, I had some experience once, That an ICO couldn't  reach its hard cap and in the end had to stop the ICO and then returned the investment they accumulated from investors I really think they are quite honest with their apology because for almost 12 weeks or less we didn't get the payment we deserve and just had to accept the fact that this is a reality for certain bounty hunters their are certain risk involve and you are accepting this by joining a campaign.