S. short [u] often became [o]; [ŭ|uC{uw}|u{mnŋ}] > [o|uC{uw}|u{mnŋ}]

S. medial [j] became [i]; [-j-] > [-i-]

In Sindarin and Noldorin any surviving medial -y- [j] became i at some stage. This is a factor in Sindarin orthography, where i always represents the vowel [i] medially, but at the beginning of a word before another vowel represents the “y”-sound [j], because it is the only place where this sound can appear:

S. [ɸ], [β] became [f], [v]; [ɸ|β] > [f|v]

S. [iu] and [ju] became [ȳ]; [{ij}u|jui] > [ȳ|jui]

Do you think péti "lips" could be a model how CV monosyllables form their plurals? I mean like pé - péti, ré - *réti, thé - *théti, possibly pí - *píti etc

It's a wild stab, I know, it just occurred to me.

S. [x], [ɸ] vocalized between a vowel and [s], [θ]; [Vx{θs}|Vɸ{θs}] > [Vi{θs}|Vu{θs}]

S. [ɣ], [ŋ] vocalized before [l], [r], [m], [n]; [V{ɣŋ}{lrmn}] > [Vi{lrmn}]

S. voiced stops became spirants after vowels; [V{bdg}] > [V{vðɣ}]

I will start working on a new release of Atanquesta in the coming weeks. I plan to

• expand the grammar explanations and add even more examples

• rework the dual nouns section to better reflect current consensus

• add questions/exercises at the end of lessons

I don't know how long it will take, depends on my job, life etc. I will of course make an announcement when ready.