Official (and as far as I can tell, actual) line is command requirements for the 146 will be met from within.
If you are already P1 on the 146, you may well be offered EMB145 DE P1, as it would never hurt to have dual rated pilots at the company's disposal.
Although a little behind on the salary scale, they have a reasonable catch-up program in place.
Nice bunch of guys on both types, see you soon ...?