Answer:

This is a "high level" question, so if you are not serious about wave theory, don't continue.

The post-pattern action following a Diametric is not dependent on the Diametric itself (as with most other wave formations), but relies on the larger pattern the Diametric concludes. For example, did the Diametric end wave-A of a larger Flat or Triangle; was it wave-2, wave-4, wave-x, etc.

In order of priority, these are the things you can expect following wave-G of a Diametric. The wave right after wave-G will be larger and faster than any "same direction" leg that occurred during wave-G. Next, if that post-G-wave is also larger and faster than waves-B, D and F within the Diametric, then the Diametric ends a single leg of a larger formation.

If the move after wave-G is not larger and faster than waves-B, D and F, then an X-wave is probably forming. Otherwise, the Diametric will be one leg of a larger, ongoing pattern OR it will be wave-1 or 3 of a Terminal formation.