Aww, Pete! What a disappointment, I know. I've had some carefully planned tours that didn't "happen" due to forces beyond my control, and I know what a disappointment it can be. I'm sorry.
Well, the good news is, "Next Year" is just a few days away, so I'm hoping the trail mud may yet drain away and make your route ridable.
<nods> Yes, a loaded bike doesn't allow the handling leeway of an unladen one, and you are very wise to wait till conditions improve. Better to be safe than sorry in this case; good on ya, Pete!
Life will go On
Yes, disappointing, I know, but you've bigger things ahead in your future, so a bit of a wait now or even a rescheduling for a much later date is probably better in the long run.
Hang in there!
All the best,
Dan.