A user changing their email after signing up and verifying it can change it without verification in profile settings. The configuration option "verifyemailenabled" will only validate email only on sign up.
{ "binaries": [ { "binary_version": "2.6.0+dfsg-1", "binary_name": "grafana" }, { "binary_version": "2.6.0+dfsg-1", "binary_name": "grafana-data" } ] }