support contact for all the tech support services are provided here.
Office updates remain free whereas office upgrade is a change of version. Normally office 365, being a subscription based version allows you the free upgrades but standalone products do not allow change of version for free. Life time get the security patches for free for life time but not the change of versions.
In general, the Manufacturer says 60 days free support applicable for the office products. Although the service depends on the type of issues.
Office product suites are released as subscription based versions and standalone proudcts. The subscription versions contain recurring fee for the licensing wheras the standalone product is a one off payment.