OK Penske
Imagine for a moment that a NTC went out advertising pax commands (of course this doesn't need a NTC because you're assumed to have applied when you joined the company, but bear with me). The successful applicants (Cat A F/Os) were then allocated command courses in seniority order.
There are training resources available but these courses have now been cancelled.
The -400 courses can be filled by either type of applicant. Both types of F/O applied and were allocated courses in seniority order.
Taking the freighter applicants first is slightly cheaper for the company, but is it still right?