A family of grammars for Voynichese

[Grove]

Don’t e’s only precede d’s , or o’s or a’s and that a’s only precede r’s l’s and n’s (or i benches)? I see the a as a transition from e to  i series although there are cases of o’s followed by i series without the a transition.

I feel like the e ee eee series preceding a d act in a similar way to the i ii iii that precedes the rln variants.