This is the difficulty we are facing now for our son, since he will start P1 in 2021, we need to determine if we really want to pursue local school with non-english medium of instruction this year.
Local friends tell me that if I pursue a local school, then my son will need go straight to high school with the local chinese exam which is very difficult even for them.
Another issue is all of my son's classmates do not speak english so sometimes my son feels isolated specially when going to school trip where no one speaks english.
Feedback from expat friends also say that they try to go to chinese local school in K1 but they eventually decided to move to english school and observed that there is a big difference in how happy and active their son was in learning after the move.
Maybe it's a case to case basis but I know my son is not really interested in learning Chinese language.