Name another area, aside from District 27, that has the most executive condominiums.

Aside from District 27 (Yishun and Sembawang), Punggol and Sengkang are areas with the highest concentration of executive condominiums in Singapore. Both towns have seen a significant number of EC launches over the years and host multiple EC projects in close proximity. This cluster of executive condominiums makes Punggol and Sengkang stand out as the main hubs for ECs beyond District 27.