What you wrote is not correct.
CIF - Southern Section (and the others) prohibits players competing on a HS team from "competing" in the same sport during the HS season for that sport, which means HS aged players cannot play on Rec, Club, ODP, ECNL, DA, etc. The DA prohibits DA players from competing on a HS team while rostered on the DA team, unless a waiver is given by the DA.
The DA does not go on break during the HS season (like club soccer), thus, active DA players have to be released from their DA team to play HS and under the DA rules, cannot rejoin the team until the following season.
The CIF has no rules preventing DA players from playing HS, except the general prohibition against competing on an outside team during the HS season.