Sometimes producing this document will result in agreement. If so, great!

But if it doesn’t, email it to your managers.

If the authors report to different managers, the document should be sent to both managers.?

The managers might decide to call a meeting.?
If escalating to a single manager, the expectation is that they’ll make a decision. If escalating to multiple managers, they’ll hopefully decide together. But if they can’t reach an agreement, they should raise the issue with their respective managers recursively (possibly adding more context to the unblocking doc) until a decision is reached (or the stack overflows).?