I am Premium and sold 3072 m on Aug. 24, 2018. I still own 7680 m and the amount of land has changed in my account, but not the cost which was $67.00 USD last month. My land was claimed Aug. 5, 2018. Does this mean that my tier will remain the same, at $67 USD on my next tier payment date and not change till October? Thanks very much!