American Express and Escape Lounges have made changes to the rules regarding Platinum card access. You now need to arrive within 3 hours of your departing flight.
Effective May 9, 2024, to access select Escape Lounge locations, eligible Platinum Card® Members will be required to arrive at the lounge within 3 hours of their departing flight. During a layover the eligible Card Member may use the Escape Lounge in the connecting airport at any time. Additional information on guest fee rates, access policies and lounge terms and conditions can be found at escapelounges.com/us/access/.
Seems like a sensible change if overcrowding is an issue. Obviously annoying if you have a long layover though. Layovers are fine according to the terms.
Hat tip to YMMV