CO's DEL-EWR makes very very few diversions. It's within range even in the middle of winter. This past winter, only time it MAY have diverted was Jan 16. The 4/9 flight went to Gander, but I can't remember the reason.

In short, not an issue. I have not heard of restricted load on this route, so you won't get stuck in DEL. They just make a fuel stop in Goose Bay, Gander or somewhere.

In fact, CO is starting BOM-EWR this winter, which has even longer flight time.