alternating blinking tower lights

Hi all,

I am trying to set up alternating blinking lights on an animated tower. I am using a material instance and I am trying to pipe it through a blueprint, because the lights should not start blinking until the tower is activated. There are about 10 lights on the tower, but I don’t want them all to blink at the same time, so I set up material 2 instances, to have a bit of variation.

Once the player enters the trigger volume, the tower extends and activates and the lights should take turns blinking. This is what I have so far:

I tried installing a delay between the two lights - the material has a time and sine node, with 2 second interval - so I made the delay 1 second. No matter what I change the delay timer to, they all blink together. Even if I set the delay to 19.5 seconds, once the timer runs out, they still blink together. Am I wiring these nodes wrong, or is there a better way of going about this?