This is kind of a banal story. I'm the lead developer on a "modernization" project that's taking a lot longer than anticipated (you see where this is going). The team is great, it's just that the work is way outside their comfort zone. The business has been selling the new version pretty hard and we're not going to make the release (about 3 months to go). Question is; as a lead how would you handle this? I think my direct manager has a healthy dose of skepticism about the timeline, but the product owner doesn't. At what point should I start sounding the alarm? I'd like to give it a couple of weeks and see if the team picks up pace but I'm not confident.