Hi,
With my DS4 I ovulated on day 42... With my daughter it was day 18 or 19 (clomid baby). I'm on clomid now and still don't think I have.. it's day 18. My thoughts are that if your body stimulates the follicle later in the cycle it's not really a mature egg. If it starts growing normal time but then gets released late then I'd guess it'd be "old". I guess it depends on your own body. Not much help am I? But I just want to reassure you that late o's isn't all bad!