If under the provisions of the governing instrument, property which is held in one trust (the “first trust”) is to be transferred or poured over to, merged with, or otherwise combined with property in another trust (the “second trust”) and property in the first trust is subject to different treatment for purposes of the GST from the property in the second trust, the fiduciary of the second trust is authorized, but not required, to retain the property in separate trusts in order to preclude or minimize the imposition of the GST upon transfers from either or both trusts, with other terms of each separate trust being substantially identical in all respects.