pcnewtone

Sorry if this has already been answered, but I can't find it, so here goes... I just got a Premium account, and hope to purchase land with it. Initially, I got a Linden Home with it, but wonder whether, if I leave the Linden Home and don't use the tier for a few months, does it accumulate in my account, or is it based on the "use it or lose it" principle? Also, if I deed it to a group, does it accumulate in the group account until land is bought, or is it also lost? Thanks for your help with this. Peter (pcnewtone)