Interim reports are due within 30 days after the occurrence according to ICAO Annex 13, if I remember rightly. However, Annex 13 also says things about not commencing legal proceedings until after the causal investigation is complete, and Brazil has not held to that with respect to the Amazonian midair collision, so it is not clear that they will necessarily hold to the 30-day interim-report requirement.
However, the NTSB is reading the recorders. If there is a significant safety issue with regard to airplane systems, or their operation, that the NTSB feels needs to be brought to the attention of operators immediately, they will issue a safety recommendation on their own timetable, which means as soon as they have identified the issue. (As they did with the "TCAS INOP" annunciation on the flight display as a consequence of the midair.) They have not yet done that, and I understand the recorders have largely, or completely, been read. It is reasonable to assume the NTSB has not identified any immediate safety-of-flight issue that has to do with the AC or its general operation. Either that, or it is complex enough that no one understands it yet. But in that case, I would expect them to issue a safety recommendation that restricts operation of the affected system to within certain clearly-safe parameters. They haven't done that either.
This is a bit like reading tea-leaves. But again, if you don't see tea-leaves lying on the bottom right of the cup, you can infer it wasn't tilted to the right.
Brazilian authorities have already commented that the speed on touchdown was "within parameters" (if I remember correctly), as well as that it hit the building at a certain precise speed, so one could hope that, having partial released the landing parameters they would see fit to publish all of them in the interim report by 16 August.
PBL