I have same problem on sendto with ipv4. The code works well with iOS 18.0 simulator on Sequoia, however, sendto returns -1 on macOS Sequoia. Privacy - Local Network Usage Description is set in Info for both iOS and macOS. This privacy setting doesn't affect to this problem.

I have same problem on my M1 iMac. There was no such upgrade problem on my Intel iMac. I tried the upgrade from Beta 4 to Beta 5 many times. But I have never succeeded the upgrade on my M1 iMac.