its more like the request from current admin hoping things would finished before the next presidential election (you know how stuff work here) , its either fincantieri may postponed or reassigned their cruise ship division and shipyard for building naval ship first , if it was really the current admin request to have atleast 4 hull before 2024 , seeing how japanese launched two ship simultaneously near the end of 2020- first quarter of 2021 while the first steel cutting happened in q3 2019 , MHI still have possibility to bag the contract with that kind of requirement .
Mogami class can be built at the same time in two or more Japanese Shipyard (MHI, Mitsui and other) as they (the Japanese Shipyard) are not shy away to share building order with their rival as long as they can get the order done at the requested time. People who got know their business ethic would know how they are working