Isaac Saul's Tangle was one of Outpost's first customers and it's grown into a media operation.
Isaac moved off Substack in Sept 2021 to Ghost and Outpost when he had 27,000 readers.
Almost 5 years later Tangle has 12 employees, 500,000 subscribers and $4M in annual revenue, almost all from subscriptions. That came from a ton of hard work, grinding and experimenting. And Tangle is still on Outpost + Ghost, with great tech that is a tiny percentage of site revenue.

There's a lot to be learned from what Isaac and his team are buildingm and I strongly suggest read more about that here in the case study/interview by Lex Roman.

But here's a bit from the Press Gazette profile.
Conversion through upsell emails
A key driver of Tangle’s 16% conversion rate is its upsell emails with an informal tone, said Saul.“We’re really good at [converting] because we tell people a really personal story about what we’re going to do with the money and why we need it,” he added. “We are able to maintain that conversion rate by – [either] once a month, once a quarter – reaching out to our audience and asking them to support our work.”
These upsell emails lean into a more informal with subject lines such as “yes, I’m asking for your money”.

