It just happened. She laid another egg at 6.45pm on top of the white cabinet. I saw her arching her rear and this seemed strange. Then I saw she laid an egg. Its not very clean place there

I presume, I need to put nestbox back to her cage with all the eggs in it? 4 total by now.

a dramatic moment - she flew back to the top of white cabinet, she looked everywhere for her egg and it wasn't there!!! She even looked down below to see if it fell. I feel like I removed a newborn from the mother.
I still feel relieved because the egg isn't missing anymore.
I guess another option would be to put all her eggs inside the cage without the nestbox, right?

The chicks had so much fun when parents were not stuck in the stupid box!!!

I think that birds are fulfilling they breeding instinct when they get real chicks, not just eggs. They are supposed to have 2 clutches but they only have 1 clutch of real chicks, probably this is causing them to want one more. Can this be true? Or, is it much simpler?

They won. They got it back. And they are HAPPY. Both sitting inside, and Trillie playing his drum solo. I hope the eggs didn't get damaged or anything. Was it right? The time will tell.

I understood about removing the nestbox after the second clutch, but who determines when its time to put it back after a few months break? Do you see signs of courtship (my hen wants some love like crazy at this time) and give them the nestbox or do they start mating and then get the nestbox?

Since she was continuing to lay eggs, giving the nestbox and the eggs back to her was the right thing to do. Two clutches per year is the limit that humans have determined is safe but the birds aren't keeping count. Even if the second clutch of eggs had hatched successfully, it's likely that they would want to start breeding again when those babies were older.

Now that you know how to candle the eggs, you will be able to find out sooner whether they are fertile. If they are NOT fertile, then I would start using the hormone control techniques in a very serious way when the eggs are about a week away from the expected hatch date. This will help reduce the possibility that the parents will want a new clutch when these eggs fail to hatch.

All the flying around is probably due to the babies. At this age they are very eager to fly, and when they fly the parents tend to fly too. If it's actually the parents causing the flying, the situation will probably calm down now that they have a nestbox to attend to.

certainly the parents were troublemakers yesterday. Chicks are trying to take naps during the day, they are pretty calm.

Both parents spent a night with the nestbox but not IN the nestbox. So they may not even accept it back/

strange - when they both were not inside, I opened the box and didn't see any eggs. Does it mean they hide eggs from me or what? Is it OK for the eggs?

Now life revolves around their cage, of course. All the chicks are on top of their cage, waiting for the parents to take them to eat.

The parents are NOT on the eggs. Maybe their hormones level decreased so my attempts were actually working out?

I don't understand why chicks get inside the light fixture with the light on (its bowl shaped, made of plastic, and they can get burned). I had to turn it off, but there is no overhead light (I entirely hate this feature in US living rooms!!!) so its pretty dark without lights.

Our hen looks really tired. Probably last days battle for eggs took all her forces. She is very quiet today and looks sleepy. Its not going to be easy to see if she lays another egg tomorrow or not, because eggs are hidden (burried) in the nestbox. They come inside sometimes, but not staying in the box. The cock is not incubating because she is the one who decides.

I was at the bird store today. We saw baby cockatiels that they got from somebody (they are a few days younger than mine). Their wings are clipped! When I asked, they said its really hard for them when birds are learning to fly because they are really fast on take off. So they clip them early, which is bad as I understand.