Why is deleting the first log entry in an EVTX file more complex, and what alternative method does the article suggest?

The standard length-modification approach fails for the first log because there is no preceding log to merge into. The article suggests an alternative that manipulates the Binary XML format within event records, modifying fields like written date, template definition, and data size. This method also works for intermediate and last logs, demonstrating that deletion techniques are not unique. For implementation details, refer to the open-source code provided in the article.