Q.relocating grape hyacinths
I bought my bulbs because they were on sale. I will plant them soon. Next spring I’m creating a new garden and would like to transplant them from where I plant them now to the new location. When should I transplant them?

Yes, you can divide and transplant them just about any time, depending on your location. Grape hyacinths are quite hardy and take transplanting well as long as you provide the proper growing conditions and care. Here is an article that you may find helpful: https://www.gardeningknowhow.com/ornamental/bulbs/grape-hyacinth/planting-and-care-of-grape-hyacinths.htm
You can minimize their spread by removing the foliage and any seed pods. This will keep seeds from being spread and weaken the bulbs so they cant produce bulblets.