Unfortunately we didn’t take the possibility of non-automatic payments into account when building the system that manages our subscriptions.
I’m afraid “sneaking” in a manual payed account would cause all sort of problems for our bookkeeping and accounting in the long run.
How about changing to a yearly subscription plan? This way you only have to deal with the credit card lock once a year.
I find it quite unusual, that your bank repeatedly locks your account after bouncing a GarageSale charge, and then lets you travel 70 miles to sort out their mistake. Doesn’t sound like great customer service to me.
Maybe signing up for a PayPal credit card and using that for GarageSale also helps?