Not yet, but it is planned.
I think I asked this before but I don't know what the outcome was on it. I have had members that purchased upgraded memberships that wanted them to be applied immediately, they wanted the extra benefits immediately. However, the default is to wait until the current membership has expired before applying the upgraded membership. I would have to go in and manually change the membership level. One solution I came up with was to have a choice for the member; "Apply membership immediately" or "Apply membership after current membership expires" and let the member decide on which one. Has this been incorporated into Cheetah?