Using a Sigil, Question

I know you "buy" your guild hall using the Celestial Sigil

my question is, can you change the hall of choice?

Say we choose, Isle of the Dead. But a week later we want to switch to Warriors Isle, can this be done?

if not can we get another sigil and "buy" another hall?

if not, can the guild be disbanded, and reformed, use another sigil, and get the hall of our choosing?

finally got our sigil and just curious as to what the terms are for picking the one you want, if it's a one time thing or what.

You can also win it in the HoH
But i think u need another sigil to change youre hall
Thats what i presume