I disagree with Walrose... אחריך is the more "correct" way to write this word (that's how it will be written in Hebrew literature). People usually write אחרייך to prevent the word to be mistakenly pronounced "Ah-cha-ri- cha".
I completely agree with you and didn't say otherwise..... Just because I said that people write it that way doesn't mean they should.
However, some people do write it that way and that's why I mentioned it.
so, a double iod יי is usually (even always ?) pronouced /ei/ /è/ ? I am not always sure about the way it has to be pronounced
Sorry I don't really see... given that vowels are pronounced differently according to the language, giving an equivalent with latin letters is complicated. Would you know how to transcribe it in the IPA ?
The first one can stand for either the female form pronounced Ah-cha-raich or the male form pronounced Ah-cha-re-cha (same is in the audio).
The second one usually refers to the female form (can be spelled both ways)