Datapoint Diu Indo-Portuguese/õ - nasalized higher mid back rounded vowel
In Diu Indo-Portuguese, nasalized lower and higher mid back vowels enter allophonic competition. There are some contexts which favour one or the other (e.g. nasalized lower mid back vowels appear to be preferred when preceded by a voiced labial-velar approximant), but overall they appear to be roughly similar in terms of frequency. As such, I have classified both as major allophones, with the caveat that their phonological representation is in fact the same.
Values 
Exists (as a major allophone)
- Example 39-241:
-
õtyesterday