Egg laying delay

[cowtown chick]

I have a mixture of hens, I got them in May of this year, the Australorp started laying about a month ago, followed by the Lace Winged Wyandotte, I have yet to get any eggs from the Speckled Sussex or the Barred Rock, the weather is like a roller coaster here in East Tennessee, It has gotten as low as 26 at night and during the day 50's-60's. The weather hasnt slowed down the hens that are laying but have yet to get any from the others. Is there still hope the others will lay before the spring?

 

[AK Baha]

How old are they? They will slow down in winter but may still lay a few.

 

[cowtown chick]

they are around 6 mos, two are producing an egg each day but the other 3 just look into the nesting box and say "wow, nice eggs"