Expressjet recently changed the code they use for ERJ-145LR’s to “LRJ” which FlightAware is currently misinterpreting as a Learjet.
They say they will fix this but it hasn’t gone in yet.
I believe Expressjet did not previously differentiate between ERJ-145LR’s and ERJ-145ER’s in their coding that was sent to flightaware. Only between ER/LR’s and XR’s.