Generally speaking, deposts to and redemptions from your Vault are possible 24/7 unless you add a policy which dictates otherwise. Caveat: Trading heavily on Synthetix and other similarly designed exchanges may occasionally make redemptions not possible because of their delayed settlement design. The Guaranteed Redemption Policy ensures that your Vault has a policy which restricts you from trading for at a set, fixed time every day so that subscribers know with certainty that they can redeem within this window. This is a recommended policy to have if you will be trading with Synthetix. If you have any questions about using this policy, come and discuss them with us.