Unfold the pined UV

Hello, I didn't upload any pictures before and felt that I couldn't express my meaning clearly. I don't think the pin UV function works well with unfolding the UV again. When I unfolded it again, the effect was quite chaotic as shown in Figure 2. In fact, even if there is a pined UV, when we unfold the UV again, it should still be in the state of Image 1,I personally have two ideas about this. 1. pin the size and position and shape of the pined UV, but when I unfold the UV later, other UVs should only unfold in the remaining space, not in all spaces. 2. Onlypin the shape of the UV. When unfolding the UV again, the pined UV will be rearranged in size and position like all other UVs.