I'm a nonnative speaker of English and I've always been unsure about the pronunciation of "i" inside words like direct, organization, etc. I was thinking that it's a matter of choice between American and British usage to pronounce that "i" as ɪ or aɪ, or even ə, but looking at some dictionaries made the situation more complex for me. For instance, MacMillan dictionary gives the American English pronunciation of "indirect" as
/ˌɪndɪˈrekt/
/ˌɪndaɪˈrekt/
whereas the British English pronunciation is given as
/ˌɪndəˈrekt/
/ˌɪndaɪˈrekt/
So both of them include two versions and ɪndaɪrekt in common. I thought that only British English had ɪndaɪrekt.
The same dictionary given the pronunciation of "organization" as /ˌɔrɡənɪˈzeɪʃ(ə)n/ for American English and /ˌɔː(r)ɡənaɪˈzeɪʃ(ə)n/ for British English.
Is there a prevailing rule in international English for this kind of pronunciation? What do native speakers think and suggest?