If you actually placed a deposit on your SSR ownership, then Members Services would have already assigned you a member number and you can make a reservation immediately. This is one of the benefits of buying direct from DVC--if the deal falls-through for some reason, they simply cancel your reservation.
If the above is true of your situation, then I'd suggest calling your Guide first to get your member number. He/she can then transfer you to Member Services to book a stay.
When you can actually begin using your points depends on a number of things--your Use Year, occupancy date of the building you purchased, closing date of the contract, etc. If you are unclear on this issue, ask your Guide to explain in detail. The exact answer will vary greatly from one member to the next.
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