IIRC the design specs for the 146 ‘STA’ tanker version included 2 wing pods in addition to a centerline hose. The concept was biased towards a fighter CAP operation, reminiscent of the Lightning days with Buccaneer support. This might be relevant today if it releases the conventional takers to a strategic role, but fighter ops would loose some flexibility.
Additional fuel capacity (considered for another ‘military’ role) could be provided by fitting a whale-back tank (over the wing fuselage) and under-floor tanks.
The weight increase up to the heavy-weight RJ 100 (proposed RJ 115) should have been accommodated in the existing design, and the later LF engines, which are flat rated, might have a ‘bump’ capability.
The receiver probe was flight tested including a limited tanker evaluation behind a Victor.