GraphQL createIssue is unable to assign a different branch than default one

[Kreestyan]

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The API to assign an issue to copilot using GraphQL API is lacking the field to direct copilot using a different branch than default one. Although as explain in this response, one can easily do so from the UI.

I understand we can pre-assign a new branch to an issue, and then eventually re-assign it to copilot but when doing so, the agent is still starting branching out of the default branch. It is not considering the associated branch created earlier.
I also tried to add directions to request the agent to create a branch from stage but it cannot work as, it seems the branch is created 1st and only then the agent starts reading the instruction, so at that point it is already too late.

This is a serious inconsistency between what can be done in the UI and what can actually be automated. As of now, my organization is unable to use this feature as we prevent our developers to change the default branch. Being able to create an issue only on default branch which is most of the time, the production branch, is not practical at all.

When do you plan to make the GraphQL API consistent with what it can do with the UI?

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