Originally Posted by i0wnj00

Yes, you could. It just requires more effort to reach your final destination since you would need to time everything right with the crossing the border at CBX, taking Uber/Lyft and arriving at SAN in time for your outgoing flight. I would budget an additional $64 for a family of four to use CBX to return to United States and $40 for the ride to SAN. Make sure you have your permits to show or surrender because the National Institute of Migration occasionally has somebody checking outbound passengers before they collect their luggage from the carousel at TIJ.

In this case you would have to cancel your returning leg back to the United States, create a new flight from SAN (or wait till you reach SAN), get a one-way ticket to TIJ, cross the border at CBX, take Uber/Lyft to SAN. Depending where you go after you exit CBX you can pick up a car rental at CBX with a one-way trip or take the Pacific Surfliner from Santa Fe to Union (or somewhere in between).

Lines aren't an issue when returning to the USA with CBX since only airside passengers can access the CBP checkpoint. Much better than using San Ysidro or Otay because you will be taking a taxi/Uber, dragging your luggage around, and waiting in line to return to the USA along with the commuter traffic.

Once you are in the USA, you can use San Diego as jump point to get back home.