Dynamics GP Support & Services blog has got the information on GP 2016 database upgrade.
Most important information among all that’s been posted, is the fact that we cannot perform a direct upgrade to GP 2016 from any version that’s lower than 12.00.1826. Not even those who are currently on GP 2013 R2 (12.00.1745). It has to be a two-step upgrade for all of them.
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