White LEDs have UV emitters that make white phosphors glow. If the phosphor degrades, then more UV comes out and the light turns more purple. Another possibility is the power supplies are failing and the voltage changes and the LEDs emit in a different band. However, if these are RBG LEDs and the R and G LED portions fail the lamps will emit blue light. Usually on purchased LED street lights the vendor does not tell you where they bought the LEDs or manufacturer. The vendor usually either only makes the power supply or buys them, and in either case they only assemble the product from these pieces.

Duke's problem is it's all probably a case of lowest-cost bidder and low quality, never tested for longevity.

White LEDs have UV emitters that make white phosphors glow. If the phosphor degrades, then more UV comes out and the light turns more purple. Another possibility is the power supplies are failing and the voltage changes and the LEDs emit in a different band. However, if these are RBG LEDs and the R and G LED portions fail the lamps will emit blue light. Usually on purchased LED street lights the vendor does not tell you where they bought the LEDs or manufacturer. The vendor usually either only makes the power supply or buys them, and in either case they only assemble the product from these pieces.

Duke's problem is it's all probably a case of lowest-cost bidder and low quality, never tested for longevity.

White LEDs have UV emitters that make white phoshors glow. If the phosphor degrades, then more UV comes out and the light turns more purple. Another possibility is the power supplies are failing and the voltage changes and the LEDs emit in a different band. However, if these are RBG LEDs and the R and G LED portions fail the lamps will emit blue light. Usually on purchased LED street lights the vendor does not tell you where they bought the LEDs or manufacturer. The vendor usually either only makes the power supply or buys them, and in either case they only assemble the product from these pieces.

Duke's problem is it's all probably a case of lowest-cost bidder and low quality, never tested for longevity.

White LEDs have UV emitters that make white phoshors glow. If the phosphor degrades, then more UV comes out and the light turns more purple. Another possibility is the power supplies are failing and the voltage changes and the LEDs emit in a different band.