What are you trying to upgrade it with? CO doesn't sell cash upgrade except for Hawaii routes. If you have CO miles, then, yes, "B" is an upgradeable fare even if you're not elite. From EWR to DEL, it's likely to be a "Series 10 upgrade". A very steep 40K miles + $300 each way from a B fare.

And what dates are you flying? It's very rare to have "B" fare but not full "Y".