Assign different time periods to different levels in Pro Sites

Could it be possible to choose 1 month/3 month/12 month options for different packages independently of each other? That is, I would like the lowest level to be available only for 12 months at a time, but the other levels users could choose between the various time periods… right now it seems that if you enable 1/3/12 month prices for one level, you have to enable it for all levels. This doesn’t work with my business plan and it seems like a function this plugin would benefit from.