There is an area in the crafting area in your home borderland where you do not get the disabled siege placement and invincibility.
Here is a picture of me standing in it: https://gyazo.com/92a226d43b6b2d1a1426f2f918d6682f
I am able to place siege if I stand in that spot. It’s very precise, if I gave my movement key a tap I would no longer be in the area.
https://gyazo.com/6a362da74c9ad94635fe7efb1964e912