Hang in there! I know it is hard to be patient. Some of the Ameraucanas seem to mature slower. All my pullets are the same age. I have 3 diff, breeds ( 4 SLW, 6RIR, 5 Ameraucanas) Oh yea, and 1 surprise SLW roo. I received mine from Cackle Hatchery as day old chics. They were all hatched on April 11th, but matured at diff rates, even among the same breeds. One of my SLW at 20 wks old was my first to lay, a RIR at 21 wks was the second to start laying and that was it for a while. I guess at 23 wks old - 24 wks old the rest of the RIR started to lay.
I finally received my first colored egg from one of my Ameraucanas at 24 wks old. I think even 2 of them had started to lay that week, but they would skip a day (tease me) at the same time and take turns laying. They finally laid on the same day. one lays an olive green color and one lays a very light blue. Then at 25 wks one of my favorite Ameraucanas ( Brownie) laid a very light tan, pinkish egg. I think yesterday ( 27 wks old) was the first day that all my pullets laid.
I bet you will be getting a pretty colored egg soon. Keep us posted on their progress.