They changed the specifics of the protection plan. I'm pretty sure it's not pro-rated anymore (was it ever ?). I just see that the price of the plan is $8 now ???
If my math / method is correct, you have to keep it for (120) days or (4) months, so that's $32 in PP payments. If it's not pro-rated and you cancel in the first month, it's $8 + the $30 cancellation fee. See, it's cheaper to keep it.
As for forgetting to cancel it and paying more, I set a reminder