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Platform owners periodically revise the rules binding the developers who build upon them. Less is known about what happens when such a change is announced, resisted and withdrawn in full before it binds anyone. This paper studies the Unity Runtime Fee, a per-install charge announced in September 2023 and cancelled in September 2024 with no developer ever billed, through three separately collected series and a counterfactual forecast fitted only on pre-announcement months. In a monthly compositional sample of 13,985 platform projects (2,057 declaring a focal engine), the open-source alternative stands 20.3 points above the counterfactual while the fee stood and 26.4 points afterwards under the pre-specified forecast, with no detectable change at the cancellation. A jam panel and a repository series move the same way. The rise begins before the announcement, alongside a major release of the alternative, and is not separately identified once a break at that release is allowed. The shift had not reverted by mid-2026.