Change of building plan / building application

Hello,

I urgently need a competent and simple answer, in case someone has had experience.

We have now submitted the building application for a single-family house with a basement (utility basement).

According to the soil report, additional costs arise because there is pressing water (seepage water).

Even so, the basement causes very high costs including incidental costs, such as civil engineering work, additional costs for sealing, wall thickening.

We now want to briefly and concisely remove the basement from the construction project? Is this fundamentally possible due to the facts? What additional effort will we face, we have a contract with a general contractor (developer?)

The ongoing building application comes to mind here, as well as the adjustment of the building sketch in particular.

However, this should not be so dramatic since nothing has been done yet. Only the sampling is completed.

Regards

What does the contract say, from which point in time will costs for planning changes be charged by the developer? For us, we could have made unlimited changes until the completion of the detailed planning/execution planning. Or rather a preliminary stage before the structural engineer finalizes the statics. Apparently, you are nowhere near that stage yet, so changes to the project should still be possible? Or is it a model house with a basement, which would present bigger problems for the developer or general contractor?

I would definitely submit an amendment to the building application, as having or not having a basement is already significant and may also affect dimensions such as ridge height, etc.