Passover, from its introduction by God to Moses, comes with a "for all generations" and "everlasting ordinance" non-expiration date. Ezekiel 45 reveals Passover observance during the Millennium. I believe it's an ordinance and an invitation to an impartation of faith - faith that will be greatly desired during upcoming challenging times. Meanwhile the participating Church will be standing beside beloved Israel in observance, to encourage, love on and even provoke Israel to a place of understanding of God's faithfulness as well as presence.