I have family right down the road from CLD and it's always surprised me that the area has never regained commercial air service. The area has grown dramatically in the last 20 years and there's quite a large business base nearby, not to mention it's fairly affluent. SAN and SNA are both a lengthy drive from northern San Diego County. I'm not sure it makes sense for AS to start this service but I'm surprised another carrier has not given it a try. That being said, the NIMBYs in the area don't like the noise of jets so turboprop service would likely be the only option.