By 1947, M-99 was completely paved. One segment between Litchfield and Homer was converted back to gravel surface in 1952; a change that was reverted two years later. By 1960, the former US 12/M-99 concurrency through Albion was redesignated Business US 12 through the city when the I-94/US 12 freeway was completed. Within a year, that business loop was redesignated BL I-94 when the US 12 designation was removed from the freeway and applied to the former US 112; at the same time, the US 112/M-99 concurrency in Jonesville became US 12/M-99 as well.