Welcome back to the Wefugees Community and thank you for reaching out to us.
First of all, there is no general answer to your questions as there is (as far as I know), for instance, no minimum/maximum time period of holding a Duldung before getting a respective residence permit. It will depend on the individual situation and immigration offices (Ausländerbehörden) also deal with these procedures in different ways.
On the other hand, as long as you are holding a work permit, you can also work with your Duldung. There is no maximum period in this aspect either.
However, the immigration office will also not issue the residence permit automatically and you need to apply for it. It could make sense to involve a lawyer also. It is certainly a good point that you are working and generating/contributing to your and your family's income as well.
All the best,
PS.: I saw that you opened a second thread with the same content. In order to keep information in one place and a better overview I closed that one. I hope this is okay for you.