You are correct on both statements. Also, the month periods of the two plans are not likely the same (unless you bought the iPad and activated the 200 MB plan the exact same day as the start of your 1 GB billing cycle).
They are on two different iPads so they are on different cycles.
Pulling up my new (got it an hour ago) rMini account it shows that I have the "Free for life" 200mb and the "Unlimited" 1gb plan active at this time.