moving grapevine

I got a grapevine a couple of years ago which has done nothing as I think it doesn't get enough sun and the drainage is probably poor. I've got a better place for it now and will dig a big hole and improve the drainage with broken bricks etc before planting.

My queston is, having sat there for 2 years and not grown is it worth transplanting? or is it going to be stjnted somehow? It looks healthy enough, just literally has not grown at all.

Presumably I should wait til its shed its leaves before moving?

Thanks!

Moving plants at this time of year is good because, even though they are on their way to being dormant they can still get established in the current warm soil before winter.