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            <endDate>2026-08-10</endDate>
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      id="Fxbrl_20260807103003934">SEI ALTERNATIVE INCOME FUND</dei:EntityRegistrantName>
    <cef:InvestmentObjectivesAndPracticesTextBlock
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      &lt;div&gt;
        &lt;p style="margin:0pt 0pt 5.5pt 0pt;text-align:left"&gt;&lt;span style="font-size:8pt;font-family:Arial, Helvetica"&gt;&lt;span style="text-decoration:underline"&gt;Change in Investment Strategy for the SEI Alternative Income Fund&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;
        &lt;p style="margin:0pt 0pt 5.5pt 0pt;text-align:left"&gt;&lt;span style="font-size:8pt;font-family:Arial, Helvetica"&gt;&lt;i&gt;In the Fund Summary for the Fund, under the heading titled "Summary of Terms," under the sub-heading titled "Investment Approach; High Degree of Risk," the seventh sentence of the first paragraph thereunder is hereby deleted and replaced with the following:&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;
        &lt;p style="margin:0pt 0pt 5.5pt 0pt;text-align:left"&gt;&lt;span style="font-size:8pt;font-family:Arial, Helvetica"&gt;Under normal circumstances, the Fund's allocation to equity securities of CLOs will not exceed 10% of its net assets, measured at the time of purchase.&lt;/span&gt;&lt;/p&gt;
        &lt;p style="margin:0pt 0pt 5.5pt 0pt;text-align:left"&gt;&lt;span style="font-size:8pt;font-family:Arial, Helvetica"&gt;&lt;i&gt;In addition, under the heading titled "Investment Strategies," the seventh sentence of the first paragraph thereunder is hereby deleted and replaced with the following:&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;
        &lt;p style="margin:0pt 0pt 5.5pt 0pt;text-align:left"&gt;&lt;span style="font-size:8pt;font-family:Arial, Helvetica"&gt;Under normal circumstances, the Fund's allocation to equity securities of CLOs will not exceed 10% of its net assets, measured at the time of purchase.&lt;/span&gt;&lt;/p&gt;
        &lt;p style="margin:0pt 0pt 5.5pt 0pt;text-align:left"&gt;&lt;span style="font-size:8pt;font-family:Arial, Helvetica"&gt;&lt;i&gt;There are no other changes to the Investment Strategy of the Fund.&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;
        &lt;p style="margin:5.5pt 0pt 22pt 0pt;text-align:left"&gt;&lt;span style="font-size:8pt;font-family:Arial, Helvetica"&gt;&lt;i&gt;There are no other changes to the Prospectus.&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;
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