Is it allowed to lay tiles on fresh screed?

Next week the screed in the new building will be installed. Until now, I thought it would have to dry for at least 6 weeks before the tiler can start. Now the contractor says it can be done immediately after it is walkable; moreover, the tiler is available immediately and we should make sure to get the tiles.

So either immediately or after 6 weeks. Where is the logic in that, and how can the screed dry with large tiles (60 x 60 cm) on top?

He should not dry for 6 weeks, he should dry for x weeks and then the residual moisture is measured. Every room should have a small hole in the middle with a plastic rod, where the measurement is taken.

There are additives that make the screed dry faster (very fast).
This is expensive, it is stated in the construction specification or in the contract as an item.

However, something is quickly told to the builder so that the construction progresses.

btw: what is the rod for? With us, it was triangular, blue foam.

I would also consider the following: The screed should not lose moisture too quickly, for example on the top surfaces, so that it does not "sand" (my layman’s understanding). If the tiler finds it difficult to work in the "haze" and opens all the windows wide, the screed could cure unfavorably and unevenly. But can certainly give advice on what is "best" for the screed. If necessary, agree with the tiler that only the windows in the respective room are opened, but not the opposite ones to avoid cross-ventilation.

The tiler will measure the residual moisture and only start if it is appropriate. Otherwise, he would also be liable for the screed under the warranty...

Are you sure that no fast-drying screed like anhydrite screed was installed?

btw: what is the rod for? With us, it was triangular, blue foam.

Placeholder for the measuring device?!