Here’s the official blurb:
We are extending today’s scheduled maintenance for the Gran Turismo 7 servers. We ask for your patience while we work to complete the maintenance.
[UPDATED: 17 March]
Due to an issue found with Update 1.07, we are extending the current server maintenance period. We will confirm the completion time as soon as possible.
We apologise for any inconvenience this may cause and ask for your patience while we work to resolve the issue.
Gran Turismo 7 is now available for PS5 and PS4.