I personally think that selling is a good option if you are going to another hot market. San Diego is a long-term appreciation play as the housing shortage is projected out to 2050. Don't invest in the rust belt or a dying part of America as that is where CA equity goes to die. I have seen family and relatives that bought in the 70s on both coasts and property has appreciated tremendously due to housing shortage compared to the increasing population growth. I personally don't want to pay for any freeloaders, but understand that is potentially my tenant base. San Diego may only have 1.3 million people, but combined with TJ is equivalent to 5 million residents.
You also have to consider where are the growing demographic groups and where are they moving to? I see a ton of diversity in San Diego and hear languages from all over the world. The housing situation is only going to get worse in San Diego, but guess what that will do for demand? If they vote for rent control in the future, then I will still hold until they realize how it will kill investment in the region. The only construction I see around San Diego are for new homes priced in the low $600s. More blue collar workers are leaving due to affordability, but I see more white collar workers moving into the neighborhoods.
Another thing to consider is what major coastal CA city is the most affordable? It is definitely not SF or most of coastal LA. My suggestion is to hold if you can and then cash out refi and buy other rentals if your current rental portfolio can cover the costs. Interest rates are so low and for every $100k you borrow is going to add another $500 to your payment.