An RCA can be on a dual assignment both as an RCA and a Casual on the city side, but when they are performing the duties as a city carrier they get paid the casual hourly rate. From what I understand they are not represented by the NRLCA while they are working as a city carrier either. Also keep in mind that Casuals make a lot less than an RCA. I'm not sure what the current rate is though. It's my understanding that seniority is not affected by this type of assignment.
We've had several RCA's in the past who have opted to be on a dual assignment so they could work more often than once a week.
Hope this helps.
