Ilk. [ei], [ou] became [ī], [ū]; [ei|ou] > [ī|ū]

Ilk. [ei], [ou] became [ī], [ū]; [ei|ou] > [ī|ū]

These developments were described in the Comparative Tables (PE19/25), but there are no attested examples.

Phonetic Rule Elements

[ei] > [ī] ✧ PE19/25 (ei > ī)
[ou] > [ū] ✧ PE19/25 (ou > ū)