This parameter isn't working as intended so am working on a solution that removes it and replaces it with a more flexible solution. Note for current sites backwards compatibility will be applied to ensure existing options still behave as expected.
The new implementation will allow using a delimiter to apply pricing per-option to first and regular price individually. This will give a lot more flexibility and will be a bit more clear what's happening. Below are some examples of what to expect.
Apply to first and regular price: 10
Apply to first price only: 5|
Apply to regular price only: |5
Apply different first and regular price: 5|10
Basically the delimiter is just a | separating the two prices. All features with pricing will work with both. So for example you could do 50%|100% for half pricing first payment and full pricing future payments. In your cast you'd have the below for example.
0|199
0|299
0|349
A lot more clear what is happening. I've added this information to the parameter tooltip as well. Options price display will also reflect this pricing behavior. Example screenshot as follows.
Pricing display in options can also be turned off or customized with language strings (both of these are already implemented in current release). Below is a screenshot showing the pricing selection working as expected as well.
Clicking the button instantly activates the 1 week free subscription as expected as well.