This looks like an unpleasant one thanks to the uphill grade, long turn lane, and high motor speeds. If I understand you correctly, you are staying to the left side of the right turn lane. If so, this is why drivers continue to pass on your left. All I can say is what I would try, and that is get over into the right straight through lane earlier, especially since you say most traffic is turning right.

You can monitor traffic for a good chance to do this. Then signal, look again, and move left. I would ride near the center of the straight through lane, but “float” slightly as conditions warranted. (depending which side cars were on, and which way they wanted to go) I’d also use a mirror and hi-visibility vest/jersey/jacket and bright flashing lights. Be assertive and prepare for a few honks.

The nice thing about commuting the same time every day is that many drivers will become accustom to seeing and working with you, so things will get easier.

Keep us posted how it goes.