I have been in both Domicile and Equipment displacements and each have very different rules. This will be a Domicile Displacement.

Per the contract,
"A pilot will be considered displaced from his domicile when he can no longer hold a position in that domicile in his status and equipment but he can hold a position in that status and equipment system wide. When a pilot is displaced from his domicile as the result of a reduction or geographic relocation of pilot position(s) he will have the following options in accordance with his seniority:

1. Remain in his current domicile in any status or equipment; or

2. Occupy any position in his same status and equipment"

So if for some reason Mesa issues a displacement of CLT saying
"ALL" Captains and FO's Domicile displacement in a single bid, you will have to stay in your Left seat. VOL Displacement vs INVOL would not matter. Everyone would be forced out at once. You can bid VOL but it would not matter one bit. This is what the Hawaii bid was.

If they issue it in 10,20,30,40 or whatever number at a time effective for Oct/Nov etc., and don't displace everybody in the same displacement standing bid, hence a reduction in flying in that base, you would be allowed to downgrade. VOL Displacement is a factor here. If you bid VOL, you use the most junior person in your seat's seniority getting displaced to bid what they could hold, which could be a downgrade/another base as Captain, etc. before you would have gotten displaced with your seniority since you were more senior and were not within range of the reduction of the base/standing bid at that point. Another words the most senior captain in CLT will not be getting displaced INVOL in Oct so if he wanted to leave CLT or downgrade for some reason that soon, he could bid VOL and take the place of a Junior guy getting displaced and his rights as well. Make sense?

As for Vol Displacement, you are afforded the same rights as involuntary so you will not be seat locked as an FO and can rebid for upgrade per the contract. I have done both VOL and INVOL displacements to my advantage. No body really tells you this stuff. It get confusing as you noticed.