Amber bike lights can improve daytime visibility. This makes sense because white light looks similar to sunlight and amber light stands out more clearly. Being seen sooner means that drivers have more time to react. Possible situations that benefit from improved visibility include users changing lanes, traffic circles, users turning, drivers opening their doors, users waiting at cross streets, and oncoming users passing. Also, amber may be easier on our eyes which can improve safety even more.

The question is whether it's legal to use them in BC? Does the BC Motor Vehicle Act say anything about it?

If it's not legal, then a possible alternative might be to avoid strobe patterns.

Dinotte sells amber bike headlights. http://www.dinottelighting.com/LED_bike_lights/dinotte-daytime-amber-aa-headlight.htm

Video of a Dinotte amber light being used:

From local bike stores, it's getting more common for bike lights to have amber for sides. https://www.mec.ca/en/product/5053-077/Bottle-Blinky-Sidelight https://www.mec.ca/en/product/5055-194/Urban-900-Light

Here's are some custom made ones.