You can still do that in your single thread. Or make a thread for stages too. Many users on here use a single thread for MULTIPLE character updates.
Although probably not relevant, but dampir's a good example of this notion; whenever he starts a new D-styled sprite WIP, he renames the topic name by the name of his new WIP, and posts all relevant progress of it, which happens pretty much after a completed D-styled sprite project.
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