Streets and Highways Code § 18396
CHAPTER 5. Levying and Collecting the Assessment
If the lots or parcels of land, or any of them, are so omitted from any installment assessment then the total cost and expense of the improvement shall be assessed on the remaining lots or parcels of land lying within such zones or subdivisions of zones as the city shall direct in the resolution, without regard to such omitted lots or parcels of land.