This is what I did supposingly but with xcode11.0... but anyway, I will try again with the new xcode.I will maintain you informed... it happened to other people in the office so if I solve this many people will be happy ;o)
Once Xcode is updated to 11.1 please also run xcode-select --install to make sure the CLT's are updated as well. Then, you should check that xcrun --show-sdk-path gives a valid 10.15 SDK path. Chris
