QuiltingCandy couldn't have sit it any better!
When I want to use that fabric, I want to USE it and not lose any time or momentum!
Washed in hot water. Dried in hot dryer. No ironing*. Folded to fit in my stash.
All before it even sees my sewing room and is introduced to its new friends!
*No Ironing* ... likewise, lazy! Why do it twice? It will get done when I go to use it, and if I only need a small piece, chances are I will only iron that small piece before cutting and returning it to its home!
As for letting it sit unwashed .... that's the way it sits in the shops. So why would that be any difference in your home?
Likewise, washing it and leaving it for months ... there's been many a quilt made from years old stash fabric, with no detriments to the end result!
What you have not mentioned is sewing with it unwashed, present or long into the future.
There are pros and cons to all approaches. It's a discussion that has been had numerous times here on the QB, so you might want to refer to the previous threads to gather your rationale.
In the end ... do what works for you!!!!!!!!!!!