All of the previous groups will reform, so if you were in a group previously, then you will be in that same group again. One or two of these groups may have new leaders, as people step down, but the people involved should be the same. Right now I am in the process of confirming group leaders.
I suspect that Louie_Rob is right, and that there will be enough interest to set up at least one new buying group. So if people are interested in running a buying group, please PM me and let me know! We will help with suggestions, advice and a sample spreadsheet to assist, but leaders are free to run their groups as they see fit.