In some situations the wine producer does not offer Futures so you have to buy at release. Strategies on buying at release vary depending on the region you are buying.
Bordeaux
Bordeaux has the broadest and most mature Futures market. Once you’ve identified a good vintage, do most of your buying as Futures. Obviously you can pick up more on release through the retail channels. By this stage you will know if the price has gone up since the futures became available. Only buy if the price has risen. Look to buy in the first two/three years when the wine is available in the retail channel and before you have to start paying auction commissions.
Burgundy/Rhone/Port
These regions each have a number of possible IGWs. Futures are not mature in the US, and the difference between the futures you can find and when they become available in the retail channel is not great. Buy the wine, on release, from a trusted retailer.
California
California is the land of the mailing lists. For both cult and established wineries mailing lists are maintained which allow subscribers to pay for the wine before when it is in barrel and then shipped on release (or when the weather is appropriate). For the small production, cult wineries the allocations for any individual is small. The size of an allocation, in some situations, is increased by longevity on the list, and if a subscriber has always paid for a full allocation. For some of the cult wines, the waiting list to even get on the mailing list can be several years. However, this is definitely the way to buy these wines. These wines can go up significantly even in the release year, driven by their scarcity.