It used to be no more than a month, but now there are projects that have taken up to 5 or six months. It is of course absolutely ridiculous. The bounties are a service and yes, you have to pay for it.
I participated in a bounty lasting 4 months. And they say they will distribute after the bounty ends (about 30 days). But now they have changed and say that the bounty will be distributed after the public sale is over, and the public sale will start at the end of December. That is a terrible sound, it will take at least 7 months to receive the tokens and there is a risk of waiting longer