Campaign experiments often report positive effects on voter turnout. But do these effects endure at subsequent elections? Existing studies provide mixed evidence on downstream effects, and the rate at which initial mobilisation effects decay. This paper contributes to existing research by presenting a pre-registered analysis of downstream effects in a unique experimental setting. I test whether effects from a UK partisan experiment in a low turnout election in May 2017 persisted at the high turnout general election a month later. The findings show that in this short space of time, the original turnout effects virtually disappeared, suggesting that downstream effects resulting from campaign experiments can be quickly subsumed by the high saliency of subsequent elections.