I think this is no big deal, for the following reasons:
1. Today, Cielo, Bridges and those other places (and the Covenant) are all unincorporated parts of San Diego County. If the Covenant becomes incorporated as a town, those other places still remain what they are today- unincorporated parts of San Diego county. Nothing becomes part of the City of Escondido until the boundary of Escondido changes.
2. Town boundaries don’t change school district boundaries. One town can’t just say its schools won’t take kids anymore, forcing them into a neighboring school district that was never planned for them. The boards of the impacted school districts need to agree to the changes.
3. Creating a town does not change a zip code. Only the post office does.