Mh, I really don't know which of my parameters for the compile.sh are wrong, but no matter what I try the script always tells me that it tries to compile kernel 4.19.y
I downloaded the linux-odroidc1-next.config in the correct folder and ran ./compile.sh BOARD=odroidc1 BRANCH=next and also tried the parameter DESKTOP_BETA_TARGET="stretch:next" , but as you can see in the attached screenshot it tries to compile 4.19.y