i have a question concerning this picture. how long have these cakes been in the fruiting chamber?

i have recenetly put 8 cakes into a f.c. and only one cake as pins forming as of now. they have been in the f.c. for about a week. should i be looking for something that is wrong

or is this a normal time frame? when can i expect to see pins on all the cakes? what is a normal time frame for the first flush?