I wasn't there for this particular product refresh, but I heard that one product version was put on life support (critical bug fixes only, no new development),

I wasn't there for this particular product refresh, but I heard that one product version was put on life support (critical bug fixes only, no new development), and the company took some time to redefine the requirements, and re-write the software. Requirements that were held in the old version weren't needed in the new one. The new solution was less complex than the old one and it replaced, so it wasn't a straight conversion. The product was also able to leverage a lot of internal code libraries.