Some year end processes are more important than others. This is one of the important ones.
Microsoft Dynamics GP Year-End Update 2016: Payables Management
Microsoft Dynamics GP Year-End Update 2016: Payables Management – Microsoft Dynamics GP Community
Year-End & 1099Payables & ReceivablesMicrosoft & the GP Ecosystem
Archived post from 2016. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.