Building permit before completion of development

Here is an excerpt from the development plan. My property will be located in the area marked in red.

Plan road 1 with earth embankment was completed 2 years ago. The other planned roads are currently dirt tracks.
This is how it looks there at the moment:


These dirt tracks are already passable by motor vehicles. The house to the north is an old building, the houses to the southwest have been built recently. Their supply lines will probably be laid along the service road to the northeast, as there is an elementary school there.
Are the dirt tracks passable by motor vehicles already sufficient to speak of secured development?

Are the dirt roads that can be driven on by motor vehicles already sufficient to talk about secured development?

No, development does not only mean roads. Utility lines also belong to it. With us, you would not get a building permit.

So I have now spoken on the phone with someone from the municipal building consultation. According to the civil engineering office, the sewer line must be installed for the building permit to be granted. I told him about my problem concerning the [Baukindergeld]. The gentleman showed understanding – which of course initially does not change the situation. However, he wanted to consult again with the head of the department against the background that it is not necessarily about the start of construction in 2020, but only the formal approval. The building regulations of NRW provide the possibility to attach additional conditions/requirements to the building permit. I pointed this out, and the gentleman agreed. He wanted to clarify whether, in this way, an early building permit can be granted, for example with the condition that the actual start of construction may not begin before the completion of the development work.

I will call the local building consultation tomorrow, hopefully they can be more concrete about it.

And? Did they become concrete?

Here is an excerpt from the development plan.

As suspected, all building plots are located on designated traffic areas. If the corresponding plots have already been formed in the land register and belong to the municipality, a building permit with conditions for the start of construction could already be granted now.

These field paths are already passable by motor vehicles.

Only this is neither permitted for you nor your builder under road law or traffic law. Agricultural roads are generally not dedicated for public traffic.

Are the field paths passable by cars sufficient to talk about secured development?

No. But if the conditions are met that development will be secured in the foreseeable future, the authority can approve it, but does not have to. The above call could have brought clarity.

Edit: You were 30 seconds faster. The posts overlapped.

One more update: I have now called the construction consulting again, this time with someone else; they said it is basically not a problem to issue a BG before the completion of the development work, but construction cannot begin before that. I am completely fine with that. This is just a verbal statement for now, but I probably can't get much more at this point in time. In any case, it makes me somewhat more optimistic. Now only the further planning has to progress. Thanks so far for your responses. If anything else happens regarding this matter later, I will speak up here again.

Update two, I have asked again for a written answer and have received it:

[...]hereby I also confirm to you in writing that the issuance of a building permit is also in principle possible if the development work has not yet been completed. However, construction can only begin once the development is secured. [...]

We even received a reference number. We can specify this in the concrete inquiry later in the current year, then the colleagues should be directly back on the subject and also find their own statements again.

This answer pleases me very much for now. There is often criticism of authorities and municipal administration, but in this case I have to speak up in their favor: The communication was very good, on phone calls my questions were always answered thoroughly and politely and email inquiries were also responded to quickly. From what I gathered in initial phone calls, it is actually common practice there to only issue a building permit after the development has been completed. Normally there is probably nothing against this, because what is the use of a building permit if you still cannot get started. However, they showed understanding towards me and apparently are trying to accommodate me by deviating from this.