There's another thread with tail numbers of aircraft with updated interiors. Progress is definitely picking up.

Also, FLL seems to be a common point of re-entry for the newly updated ships. Like today for example, updated plane ferries down from GSO then operates AS33, and the inbound AS38 SEA-FLL aircraft hops up to GSO for a while to be refurbished.

In that sense, the FA on the OP's flight could've been basically right. That's his or her office, so it's really like a "new" 737.