Not necessarily. Overlapping just means that it's found in the same environment. It could be contrastive (different phonemes), which means that the distinction can affect meaning and we should be able to find minimal pairs (or triplets), as we do with Sindhi bilabial stops. Or it could be free variation (same phonemes), which means the distinction doesn't affect meaning. For example at the end of words in English, we find both voiceless released stops and voiceless unreleased stops; however, the meaning of the words does not change.
nice video.
sir if its overlapping it means diferrent phonemes right?
Not necessarily. Overlapping just means that it's found in the same environment. It could be contrastive (different phonemes), which means that the distinction can affect meaning and we should be able to find minimal pairs (or triplets), as we do with Sindhi bilabial stops. Or it could be free variation (same phonemes), which means the distinction doesn't affect meaning. For example at the end of words in English, we find both voiceless released stops and voiceless unreleased stops; however, the meaning of the words does not change.