Financing contract before building permit?

Good evening,
I have been reading in the forum for a while now, but I could not immediately find a topic that fits my concern.

My situation from which my question derives:
We want to convert the old stable adjacent to the residential building (which is still encumbered in the land register) into an apartment for our son. A positive building inquiry is available. After we found a general contractor who is currently having the building application and/or the change of use prepared by the architect, we have simultaneously been working on financing. The inquiry went unusually quickly and positively without us having to present a building permit for financing.
Now they want to finalize financing with us even though we do not have an approved change of use/building application.
The advisor said we need to sign the contracts within the next 10 days; otherwise, they would no longer be valid. When I asked why, he said, "What could happen? The building is already standing." Honestly, I already feel somewhat pressured. I have the impression that the advisor just wants to get the contract signed.
My question: What do you think? Something seems fishy, right?

What is wrong with that? I suspect that most people arrange their financing before the building permit. You have a positive response to the preliminary inquiry. So it can only be that you have to change something (my opinion).

The time pressure that the consultant creates and, in case of non-granting, the risk of non-acceptance compensation!

The consultant will only tell you "Interest rate xy can only be maintained for this long" after which the cards will be reshuffled.

The time pressure is not okay. The bank will feel bound to the interest rate condition for 14 days. After that, a new interest rate may have to be determined. So what... if it doesn’t hurt you if it becomes a bit more expensive or cheaper, I would wait for the building permit. Especially since you apparently can sleep better with this option.

Would also wait there or use the 10-day acceptance period + 14-day withdrawal period

However, if nothing is there yet, [WIEDERRUFEN]