...I'm struggling with single digits up north today...so I can't give you any real valuable info that you asked about. I would imagine your temps are much warmer than that.
Hand watering is always best. You're right there looking at the tree and soil. I might think about a sprinkler system if I couldn't be there but only for a few days at most.
With this last batch of cold weather I would have thought that all my maples would have dropped their leaves by now but that isn't the case. Basically, around here this time of year you just don't want the roots to dry out if there are no leaves for transpiration to occur. In my case, each maple is going to have a different watering schedule based on location, pot size and soil type. I would wait until next month (March would be better) to repot if you're going to prune the roots. The best indicator to repot is when the buds begin to swell and are just about ready to leaf out. Still, you can repot next month just be cautious if cold weather (below 35ish degrees) comes though the area. If that happens bring the maple into a garage or area that stays above 35. Good luck!
