There are a few districts that defy the close correlation but they defy it consistently. The Central Valley districts, CA-10, 16, and 21, will have a more Republican result than the spread of VBM returns while CA-36 and 52 tend to have a more Democratic result than VBM returns.
Here is where PDI is keeping track of ballot returns. Returns have been very strongly Democratic, even more than the primary. That bodes poorly for Republicans but we should keep in mind that it's very early and a small percentage of ballots have been returned. Some counties have barely reported any being returned. California ballots are counted by counties and they each have their own pace. I'm not going to do a deep analysis at this point because so few ballots are in. But Democrats should be encouraged.