If someone were to become a new hire FO on the ERJ is there any sort of policy prohibiting moving to the CRJ either as captain or FO? I know seniority dictates that stuff but wasnt sure if there was company policy to keep an FO on the same equipment for a certain amount of time after training if they wanted to switch aircraft.

What are the most junior bases for FOs to hold a line on the Embraer? When was the most junior line holder on the Embraer hired?

Thank you for your help.