Just like riding a heavier bike for training rides then switching to a light bike for a race, you'll definitely feel better about it. There are still a lot of other things that might make your performance numbers not much better. One of them being if this is the only long ride or even short ride you do between now and the fall.

My son lives just outside Denver now. When this COVID thing is done or they get a vaccine, I'm looking forward to going out there and seeing what it's like to cycle there at 5000 to 6000 feet. However, from my flying days in unpressurized aircraft, I never thought 5000 feet very high for physiological stuff.