Is it legal for cyclists to use amber bike flashers for visibility (in BC, Canada)?
BC Canada

https://engineering.ok.ubc.ca/__shared/assets/Bike_Sense-Nov0552189.pdf
says


  After dark, all cyclists are required by law to have a front white
  headlight visible for a minimum of 150 metres, a rear red light
  which should be visible for a minimum of 100 metres, and a
  rear red reflector visible for 100 metres when directly illuminated
  by a car headlight. Many rear red bicycle lights sold currently
  are also designed to function as a reflector and are legally
  acceptable. Flashing red rear lights are also acceptable. Lights
  and reflective devices come in a wide range of shapes, sizes,
  colours, and costs and should be mounted directly on the bicycle.


There's an implication at the end that body-mounted lights are bad, but whether that's law or a suggestion is not stated.

There's no stated restriction on colour.  The only mention of flashing relates to the rear light which is permitted.

http://www.icbc.com/road-safety/sharing/Pages/cycling-safety.aspx says


  Your bicycle must be equipped with a white headlight visible at 150 metres and a rear red light/reflector visible at 100 metres


https://www.thenoteup.com/single-post/2017/02/28/Helmets-and-bike-lights-BCs-cycling-laws reiterates the same.  Neither make mention of flashing fronts.

ANSWER Ambiguous - but you're unlikely to get in trouble for the colour of your lights.  Flashing seems to be conspicuously absent for anything but rear lights.