下面是我在一律师网站上看到的一篇文章，现在很想确认这种说法的正确性。 文章说从学校的H1B转到企业的H1B不需要等到10月1号而是可以开始工作upon filing of the cap subject H-1B petition，可我在网上又找不到文中说的USCIS的这封信，俺的律师也一口说必须等到10月1号，和您一个观点。唉，我郁闷啊。 您再给看看？
谢谢！！！！
“USCIS has issued an opinion letter on May 23, 2007 that answers a common question: Whether a H-1B worker who is employed by a cap exempt employer can switch from cap exempt employment to cap subject employment after filing of the cap subject H-1B petition in a period in which no H-1B visa numbers are available.
The answer to that question is YES. Consider this example: A scientist is working for a cap-exempt university in H-1B status valid through June 2008. A private company (cap subject employer) files a cap subject H-1B petition for him on April 02, 2007 requesting a start date of October 01, 2007. There is a underlying labor condition application valid from April 02, 2007 to April 02, 2010. Under H-1B portability provisions of AC21, the scientist would be able to start legally working for the cap subject employer upon filing of the cap subject H-1B petition. In other words, the scientist would be in employment-authorized status from April to October, until the start date of the H-1B petition. ”