Amber is often used for daytime because it is too dark for night driving. I think the better choice for night driving is canary yellow with an anti reflection coating on its lenses which can not only improve the night vision but also reduce the glare so that the driver can see more clearly.
Amber is too dark for night driving and it is often used for daytime driving. It is better to use bright color such as yellow which can improve the light contrast with an anti reflection coating. That really improves night vision and help eliminates glare from oncoming cars and street lights.