Dateを日本時間で作成する方法です。
<div class="code-block-container"><pre class="language-js"><code class="language-js">const dateJst = new Date("2024-03-01T08:00:00+09:00");
console.log(dateJst); // Fri Mar 01 2024 08:00:00 GMT+0900 (日本標準時)
</code></pre></div>参考 
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[JavaScript]Dateを日本時間で作成する

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