
First, I built a nest box out of plywood for them all to sleep in, filled with strands of burlap. At first the two young ones didn't join but eventually they all started spending the night in there. Here's a picture of a few of them coming out:
Next, I read, or thought I read, somewhere that sometimes a pair will prefer their own nest for breeding and, more importantly, babies can be neglected in a crowded nest box. So I built a second nest box, this time with a built in perch and a better way of attaching it to the cage (the first one was just a box, and I had to attach it with some brackets).
And a couple of mornings later I find the young pair in there together

Now for my questions.
Are these finches old enough to be breeding?
All of the burlap strands have been pushed to the sides, should there be something else between the plywood and the potential eggs?
How long should it take, and if it doesn't happen what can/should I do to encourage breeding?