You can't move the cukes,

My goodness, that is very "definite"!

Yes, and for a reason . Cukes are very very un-forgiving of having their
roots disturbed. As Ann said, if you dig up a huge rootball and if the
plants are young enough, you can get away with it. At the stage yours are
at, I'm not sure how big that root ball would have to be, probably quite
large, and you would have to be carefull that the root ball is intact and
does not shift internally. If you damage too many of the roots, the cukes
won't recover. Try it - dig up one or two, try a 12" rootball, and see how
it does. I have a feeling that 12" is not big enough, you may have to go out
18" or more.

I moved a small sunflower yesterday by digging up a 6" rootball. Poor thing
didn't last through the day. I would not have thought that sunflowers that
small would have that extensive of a root system already, but I was
apparently wrong. OTOH, tomatillos are hard to kill - I've pulled them out
and dropped them on the ground, and they survived and continued to grow.

Where are you?

I'm in So. Calif coastal, Zone 24/8.

Maybe the difference in locations has a bearing?

Lebanon, Oregon. Summers are hotter here then in the So. Ca. coastal zones,
but winter starts earlier. OTOH, if you are close enough to the coast, you
don't get much of a summer as it is. So, if you are not too close to the
water, it is not too late to plant short season corn. I don't know how well
corn does in the foggy cool wet beachfront weather.