I have the following problem.
All the plans are recurring and the current/active plan is in the middle of its duration.
In frontend, I see the list with the upgrade options.
The options for downgrade have zero price.
The options for upgrade have price calculated by the rule "Keep duration, price prorated from upgrade plan".
When I select an upgrade plan with price (e.g. €296.01), I go to the "Change Subscription" form but the price is zero (in other words the field "Regular subscription price" is zero).
Could you please find a solution for this problem?