After 365 days your contributary benefit will end and you will be reassessed for income-related benefit. Even if you are not entitled to this, your claim will remain open and you will still have an underlying entitlement to ESA. During this time your NI will be credited to you and you should expect to be reassessed (which might include a face-to-face assessment)at intervals. If your claim does remain open like this, it will be possible for you to enter the Support Group, and receive payment again, if your condition merits it.
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12 Month Limit for contributary ESA