Currently sitting at 98% rated power, which I’d consider online and operating at nominal conditions. https://www.nrc.gov/reading-rm/doc-collections/event-status/reactor-status/ps.html

Hope all goes well as they transition from testing to steady state operation. Historically, Cycle 1 has has been rough for many units due minor latent equipment issues and uncaptured debris from construction. Unit 4 should have initial criticality late this year as well!