Yes, it’s possible they will wait or may lay soon.
Length of daylight does impact chickens, even blind chickens. There is a pineal gland in their head that senses light. As daylight decreases, it signals to their body to slow down, molt, stop laying. However, yours are right about laying age, and I’ve had them start laying at this timeframe, or even Nov, when I’ve had similar age chickens. Some breeds may wait until daylight begins to lengthen after the solstice in late Dec.
FWIW, I’ve lived in the Sea-Tac area, and in the Willamette Valley. In my experience, the WV get more overall light than Sea-Tac , or really most of western WA, in the winter months. Now I live in W Central Ohio, and a few years ago it was so overcast and dreary for very long stretches that winter it was very like living in Sea-Tac area. Despite having a light on a timer in the coop to boost day length (trick their pineal gland), they all stopped laying, even the young/new layers -it was that bad.
It may help to add light in the coop, but it needs to be on a timer so it is regulated amount of light, predictable. Aim for 14 hours/day. We have our timer turn on early morning, off around noon when daylight is more intense in winter, then they roost at natural dusk. Others feel strongly about not using supplemental light, so to each their own, and you can decide for yourself.
