Planning board: Dragging an issue from one fixversion to another should *only* remove the fixversion it is being dragged from, not all other versions

Use case:

ISSUE-1 belongs to 2 fixVersions:
"Thing A - Release 1.1"
"Sprint 2"

(It also belongs to a component called "Thing A", but this is not particularly important). These two JIRA versions are being used to track the current sprint and also the overall version release.

If the issue is dragged from version "Sprint 2" to version "Sprint 3" in the planning board, the association with "Thing A - Release 1.1" is lost. This is bad! Not only are we losing information, but it is lost silently with no indication to the user.

It was suggested to me by a colleage that this can be handled by using GreenHopper's version "Master" feature: if we made "Component A - Release 1.1" a master of "Sprint 2" and of "Sprint 3" then moving this issue from Sprint 2 to 3 would retain the assocation with "Thing A - Release 1.1".

However, this only works if all items in your sprint are associated with a given 'master' version. It does not work if your project has multiple concurrent arallel release streams, and issues for more than one of those streams are being worked on in a single sprint. For instance, if you have two components, each component may have their own "next release", as a JIRA version:

JIRA version: "Thing A - Release 1.1"
JIRA version: "Thing B - Release 2.7"

(Note that this has nothing to do with JIRA Components - it makes sense that issues under "Thing B - Release 2.7" would also be associated with a component called "Thing B", but this is orthogonal to versioning and use of the Planning Board in "versions" mode).

In this scenario, we're working on both of these components towards their respective releases in all of our sprints, e.g.:

ISSUE-1 belongs to 2 fixVersions (as before):
"Thing A - Release 1.1"
"Sprint 2"

ISSUE-2 belongs to 2 fixVersions:
"Thing B - Release 2.7"
"Sprint 2"

If I make "Thing A - Release 1.1" a master of Sprint 2, then dragging ISSUE-2 from Sprint 2 to Sprint 3 loses its association with "Thing B - Release 2.7".
If I make "Thing B - Release 2.7" a master of Sprint 2, then dragging ISSUE-1 from Sprint 2 to Sprint 3 loses its association with "Thing A - Release 1.1".

i.e., we get exactly the same problem as originally described.

I can't make both of them a master of Sprint 2 since this is not supported by GH. It would not make sense to support it either, because that would imply that ALL Issues within Sprint 2 belong to both of the releases - this is clearly not the case.

Therefore the only correct solution I can think of is to ensure that dragging from "Sprint 2" to "Sprint 3" only removes the association with "Sprint 2" and adds association to "Sprint 3" - and does not remove any other existing fixVersion associations.

The only time it may be acceptable to remove fixversion associations is if you manually do a "synchronise".

Thanks,
Baris.