OWOX BI launched their AppSumo promotion in October, 2019. OWOX offered lifetime access to their basic plan subscription for $49 instead of $720 per year. This was to help their business break into the US market.
The promotion led to 1,000 sales and $50,000 in revenue.
They shared more at How to Launch a SaaS Product on AppSumo: Our Best (and Worst) Moments. They share their lessons learned towards the bottom of the article.