I missed the airdrop by like half a day so I think I have a pretty neutral approach on this, with no coins at present.
An airdrop is a freebie, the rules can be whatever you want and if you have to amend them at any time that is 100% fair game. I do have to say the fact the airdrop ended so fast confuses me as to the actual point of the airdrop. But hey, however they want to run the airdrop is still fair game; it is not something you provided a service in exchange for, but a handout.
For a bounty, when you change things after the fact with no warning or otherwise shortchange people, that is when you have to call the integrity of the entire project into question. Even if the service or advertisement you provide is entirely trivial, that is an actual agreed upon exchange and needs to be honored. That is NOT what happened here (obviously), so I think talking about this being on the permanent record or anything... literally who cares? I get you probably put a minute or two effort into it; if you cannot put in another minute or two to finish the process I fail to understand how it turned into a problem suddenly.