In the Abydos area where Khasekhemwy boats have been excavated is a mud brick enclosure which has been described as a pre-cursor to Djosers complex. In fact David O'Connor considers this complex and the boats to be the origin of the pyramids.

So here we are talking about the end of the 2nd dynasty.

All of the undated pyramids from Seila to el-Kula are simply described as "possibly being" 3rd dynasty * which is totally acceptable to archaeology because pyramids without burials are a worry which is what I originally wrote.

There is nothing there to strengthen your position so there is little need to create a new subthread headed "Once again".

* Baines and Malek - Atlas of Ancient Egypt..