To clarify for OP on the back-and-forth in this thread and simplify it for OP because there is some double use of the term cancellation in how different posters are referencing the term.

OP, if you know you will travel within the next year, the best way to utilize this is to make a non-Basic Economy dummy booking for yourself** that is above the required spent amount and then wait beyond the risk free cancellation period (best to wait about 2 days) and then cancel the ticket for e-credit. You can do this twice to get both promos (statement credits). Then use the ecredits down the road when you're ready to actually book. If you cancel the tickets inside the risk-free cancellation period, the purchase would be refunded to your CC instead of as an ecredit and you would not get the statement credit.

**You can also book the tickets for your spouse under a dummy booking and follow the same steps - book a non-Basic Economy ticket above the required amount and wait at least 48 hours to cancel. Then cancel for ecredit. The thing to consider here is whether your spouse will eventually travel and use the ecredits before the ecredit expiration and of course only your spouse could use the ecredit - the ecredit could not be transferred to you.