It means that the MC POS is not fixed/static and can vary.
For me, this became the reason why I cancelled. Without knowing the POS for availability the information becomes very much less useful. I am grateful to the folks at KVS for the way they handled by cancellation and I will certainly look at it again as the tool evolves. I have always received fast and helpful responses to any questions I've posed whether on this forum on via the contact form.