MongoDB - Upgrade standalone from v3.4 to v3.6

// Set the feature compatibility version to 3.4
db.adminCommand( { getParameter: 1, featureCompatibilityVersion: 1 } );
db.adminCommand( { setFeatureCompatibilityVersion: "3.4" } )

// Test and let your application season for a while

// Once convinced everything works, then set features compatibility version to 3.6
db.adminCommand( { setFeatureCompatibilityVersion: "3.6" } )