LF - why should any airline bump you up the list for your time in the services? They don't owe you anything, they have given you the job you appled for with full knowledge of the t+cs.
In my opinion, actual flying experience accounts for only half of a good skipper, the other half relates to knowledge and application of SOPs, company politics and history etc etc, i.e big picture stuff relating to the individual company itself gained solely through experience of operating for said company.
Length of employment = Experience = Seniority, funny old thing!
Obviously there are exceptions to the rule, but I reckon this works for the majority.