Possibly 1740–1797 (Mozart-Gesellschaft and other pages?) if the "Wurmser Stadtorganisten" there referred to is the same as this Johann Theodor Greiner (see e.g. here.) 18 works by this latter 1740-1797 Greiner are listed at RISM including 6 symphonies which seem to be the same as the opus 2 from tempi, will compare incipits later.