phonology - Did the Great Vowel Shift on the long vowel /i/ occur in non-primary stressed syllables?

From the Wikipedia article on the Great Vowel Shift .

Middle English [iː] diphthongized to [ɪi], which was most likely followed by [əɪ] and finally Modern English [aɪ] (as in mice).

I think the great vowel shift on the long vowel /i/ occurred in primary stressed syllables.
But what about non-primary stressed syllables?
For example: feline.

Here's a related question.
Is the diphthong [ai] on a non-primary stressed syllable a hypercorrection?