GraceSWF Wrigglesworth

I know that tier is paid by the previous months levels - I just am trying to confirm that I've lowered my group contribution (done in SL group information Land tab) but changes aren't showing on the web and its still showing my higher contribution - which will keep my tier level high. How do I tell SL I want to drop to a lower tier level for next month? It tells me I can use a LOT more land without raising tier - but remember I want to LOWER my tier so the land available will be much smaller. I can use the calculate column to confirm that my tier will be lower, but it won't save changes nor will it allow me to choose a lower level tier area (I think because the next payment will still be at the high level based on PREVIOUS MONTH"S land owned or donated). Will the tier people KNOW that I want a lower tier (have no plans for buying available square meters) AUTOMATICALLY? I seem to be able to raise my tier but not lower it manually.