請賜教！ ICS and other IS

My son (born in Sep) will go to K2 (famous local kinder in Kln Tong) next school year. He speaks faily good english and school reports show most of his subjects, including english, in the 1st category (out of 5) this semester. His english teacher (a blonde lady) gives him very good comments to his english level.

Now we are considering to send him to IS - same reasons as most parents in this forum! Our initial targeted school is ICS. However, we realised recently (and disappointed as well) about the restriction of school age (cutoff by Sep 1). If my son wanna go to this school, this means he has to