Yes, your transactions have definitely been done after September 1st. However it is not too bad, maybe you may get a bonus for the upcoming airdrops.
I don't think there will be another UNI airdrops because so many people are now using UniSwap, but I'd like to see another exchange like UniSwap we need more decentralized exchange now, I have this feeling that Decentralized exchange and Decentralized Finance is going to be the next big thing, and people will start to adopt or embrace it.