Zeppelin, the Dash 8 Captain would have higher bidding rights on a Jetstar position than the mainline S/O. However people who would always have the highest rights on a Jetstar position would be current Jetstar pilots.
Your seniority in your own branch of the Group in preserved. You always have higher rights than anyone else to your own flying and promotions. Your rights group wide, however are based date of joining.
The GOAL lists primary function for it's early years of operation is to protect what you have now. No QF pilot willl get a Jetstar Command before a current Jetstar pilot. No QF pilot will ever be senior to a current Jetstar pilot on the Jetstar list.
No Jetstar pilot will get a slot in mainline before a current mainline pilot. No Jetstar pilot will ever be senior to a current mainline pilot on the mainline list.
Same goes for Qantaslink.
After the date that the GOAL list is finalised, any new joiners can go anywhere their seniority allows, after their freeze/bond period is finished. It is then that you will have Jetstar pilots senior to QF pilots on the list and vice versa, but they will all be junior to current pilots.
The example is TN pilots who now all have seniority in mainline for 767 Commands and they are senior to any QF pilots who joined after them on the combined list. They got their 737 commands ahead of any QF pilots. If they hang around long enough they will get 787/-400/A380 commands. There are some now on the A330 because that is a new type and covered under the Integration Agreement.
Does that explain it for you?