How to modify item description text showing on subscription payment page

How can I modify this line? I have tried altering "Payment item text" under that plan's Pricing tab and also in "Payment basket item text" in CB Paid Subscriptions: General plugin settings under the Display/Baskets tabs. None of this seems to affect the text shown in the attached image, even if I empty browser cache and refresh the page.

That's the "Payment item text" parameter found under the Pricing tab of your plans. You'll need to cancel the basket and attempt to purchase again for it to refresh as the generated string is stored with the basket at time of basket create.