Gap year - apply & defer? Or wait til next year?

My high school senior will take a gap year this fall to take a year-long international student exchange (high school, not college). My question is this: Does he apply for college admission now, and if accepted request deferral? Or wait until next fall, when his application (for admission and merit-based aid) will be much stronger? Junior year was mediocre, but this year he is on fire. Advice?

If you feel his senior year is that much better and he can still focus on applying to schools while he is on his exchange time then wait till next year. Otherwise apply now, ask for a gap year, and relook at the list of options next year,

Apply and defer. This will give him maximum flexibility and freedom during his gap year. It also leaves open the possibility to “apply” to another university during the gap year.

But also check whether the schools he wants to apply to allow deferring enrollment after admission.