I just upgraded to Supporter last night and added 200 hours to my account. I still haven't received any of the hours yet. My transaction ID is 8CB61271SX708013Y. Thanks!
Essentially the first $2 pays for the free hours you already have. This means you did not add 200 hours to your account. Payments do stack however so for the next month any other payments you add will add usable hours.
This system resembles other software services where you have to pay 'through' the free tier to access higher tiers.