You might just try calling the queen producer and see if you could get your queen at a later time. Most breeders are fully booked early in the season and any delay or order pushed back is sometimes appreciated. That way, if you get a swarm, you can then use the queen that came with the swarm, and replace as the queen producer can get one to you. And if you don't get a swarm, you can schedule to your ability to split, etc.
This seems better than ling term banking of a queen and perhaps just wasting your money.
You can bank, but over a period of time, the bees will favor the queen laying eggs, and will even propolis over the queen cage if stored this way.
And to split the package to have two queen running is really limiting the colonies ability to grow. A package will grow better with one queen compared to two small clusters with two queens.
I'd delay getting the queens. ;)