As you can see this rhubarb is not doing very well
This rhubarb isn't doing very well. Can you give me any advice on when I can move it?
Certified GKH Gardening Expert
It looks like either phosphorus or iron deficiencies. It may need fertilizer. The limited research on the climate in your country would suggest that you could move it at just about any time.
This article will help you with the care of the plant: https://www.gardeningknowhow.com/edible/vegetables/rhubarb/grow-rhubarb.htm