When Space X launches their Falcon rockets from Vandenberg in the evening it is easy to watch the launch from south Orange County. If you look toward the west about 2 minutes after the launch time you can see the rocket heading up.
Then I believe the 1st stage stops and it is very difficult to see it. A few seconds later the 2nd stage begins and you can see the rocket again but it is dim.
When the launches occur shortly after sunset the sky is dark but the plume from the rocket gets illuminated by the sun and a spectacular "jellyfish" type effect can be seen.
On July 19, 2023 there was a launch at 9:09pm. Sunset on July 19th was 7:59pm. So the launch was 70 minutes after sunset. The plume was very bright and spectacular as seen below.
On August 7, 2023 there was another Falcon launch at 8:57pm. Sunset on August 7th was 7:45pm. So the launch was 72 minutes after sunset.
On the August 7 launch the plume was quite a bit dimmer than on the July launch. So perhaps it was just a bit too late for perfect brightness.