This post uses the orthography rather than IPA because I’m on my phone and X-SAMPA is unreadable
Before /i/, the coronals /t d n l r/ palatalized to /č j ny ly n/. Before /y/, the same happened, except that (in the “standard” dialect, i.e. the one I write in) /ry/ stated unchanged. č later merged into š in all positions, and /y/ dropped after palatals. Clusters of /ny ly/ + /y/ were later restored by the shift of prevocalic /g/ to /y/ after palatals and /i/, which rule remains synchronically active: kony-gam > konyyam.
The dropping of /y/ before /i/ restored /r/ in that position: *yayri > yēni, *amuryin > amurin.