Triangle
Major Wave 4 (blue) is apparently turning into a triangle, although other structures are possible for now. I am choosing to present the triangle structure as it is one where the wave gets to be extended. As I said previously, Major Wave 4 should be a long wave to match Major Wave 2. Next week Wave e (red) should form going downwards. The end of Wave e, which may be above or below the bottom line of the triangle, will be the end of Major Wave 4 (blue).
However it may happen that the STI wants to extend Major Wave 4 further out. It can do this by making Wave e itself a triangle. The resultant structure is valid and occurs now and then.