Future Poswa
Future Poswa is a hypothetical projection of the Poswa language about 4000 years into the future, after its speakers had been overwhelmed by immigration from the Moonshine Empire. (I have also worked out sound changes for Future Moonshine, but Moonshine does not have enough vocabulary or grammar worked out yet for me to make any meaningful sentences in it.)
Sound changes
Future Poswa will change very slowly, as the conservatism that characterized Poswa for its entire history as an independent language remains firm even with the pressure of the Moonshine-speaking overclass. On the other hand, the Poswobs will adopt many words from Moonshine.
Labialized consonants are retained, but there is no longer a perfectly symmetrical setup with one labialized consonant for each plain consonant. Instead, all? labialized consonants in most positions become rounded bilabials, such that, for example, Poswa swi "I slept" becomes Future Poswa fʷi. In word-final position, and in perhaps some other positions, the consonants are delabialized instead of becoming rounded bilabials. Thus Poswa /tʷatʷ/ "lots of water" becomes Future Poswa pʷat.
Clusters are reduced somewhat, by changing them into single consonants in a process similar to what Moonshine had done thousands of years earlier. For example, pr > pf > ṗ > f. (The ṗ is a labiodental stop.)
New vowels are created from the diphthongs /ae/, /ia/, /ie/, /io/, and /iu/. These are spelled ä ä ë ö ü; that is, Poswa's /ae/ and /ia/ diphthongs merge. /ë/ probably merges with /e/ shortly after the shift.
Grammatical changes
The grammar of nouns and verbs becomes extremely difficult, because despite the general trend towards the reduction of complexity in the grammar, the simplifications lead to a vast increase in exceptions to the rules. For example, even if Poswa had 400 noun declensions, the speakers learned them all because they all followed patterns predictable from the phonemes towards the end of the word. Whereas Future Poswa may have only 15 declensions, but they are based on what the word used to look like rather than what it looks like in Future Poswa.
Likewise, the classical Poswa verb system with its many infixes was very complicated, but speakers only had to learn three stems for each verb (normal, conjugated, and oblique) whereas in Future Poswa the infixes become fusional and some verbs may have more than a dozen different mutated stems.
