Ask HN: Ever had to abandon large parts of a project 6 months in? How'd it go?

I lead a team that's put a large amount of resources into a greenfield project that's considered urgent for the business.

6 months in and we're having endless trouble with technology choices we made early on. Have you ever faced a similar decision to either stick with or throw large parts of a project? If so what did you choose and how did it turn out?