Increase retention by making it painless to switch between plans.

If a user can't downgrade frictionlessly, they'll cancel. Simple as that. Decrease churn by making it ridiculously easy to switch between tiers.

Nudge Coach's MVP didn't allow users to switch between plans. Their second-tier churn was at about 15%, but when they made downgrading possible (and easy), that quickly decreased to just about 0%. If a customer wants to spend less and there isn't a frictionless way to do so, they'll cancel. And while users downgrading may not seem ideal, it's a lot better than losing them entirely. So place each user's plan front-and-center in their account details and let them switch it with the click of a button. And while you're at it, consider offering a cheaper plan in your cancelation flow.