Wow! That looks great. I hope the citrus enjoy their new digs!
It doesn’t typically get cold enough consistently enough for us to need something similar for Lemon-san. Just about freezing temps means a move into the alcove in front of the door. Any colder and it’s a hop into the garage for one or two days. The freeze-a-gedon a few years ago was really rough on them. We had the tree in the garage and the poor thing lost every single leaf. We thought it was dead like the orange in the ground out back. But kept watering and doing the spring fertilizer anyway. It grew more leaves that later winter/spring than ever before and has been bushier ever since.
It was definitely Charlie Brown of Meyer lemon trees when we bought it. After a decade it seems happy and fluffy
Next time we have extended cold, we will just have to bring them inside and deal with the tree thinking it is spring later.