Under KeNIC's published .KE domain lifecycle, a domain that passes its expiry date enters a Renewal Grace Period of 90 days, during which the registrant can still renew through their registrar. The domain is suspended early in that window — the website goes offline and email stops arriving — which is usually how a business discovers the problem.
After the grace period, the name is deleted and released for public registration, first come, first served. At that point anyone — including a competitor or a reseller — can register it, and with it receive email sent to your old addresses.
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KeNIC's published .KE domain lifecycle. Stage boundaries and any restoration fees are set by KeNIC and your registrar, not by Onduu; confirm the exact position of your domain with your registrar before relying on any timeline.