I have been tasked with an SP2013 to SP2016 upgrade.The second server is ready with Server 2012 R2. We have software assurance licensing to allow for this upgrade.
At what point during the upgrade would the SP2013 server become unavailable? Is it possible to have SP2013 up and running after the upgrade to SP2016? We are wanting to test our custom programming prior to committing to changing users over to the new server URL. I am following the Microsoft TechNet instructions, but am unclear as to this detail. Thank you in advance!