The new much larger Seattle-Tacoma centurion lounge has now opened. The new lounge is 14,000 square feet and almost three times the size of the old lounge. The old lounge has been closed since 1/23/23 due to this transition.
The new lounge is open in the mezzanine level of the Central Terminal post security and is open from 5AM until 10PM.
Source: doctorofcredit.com