多谢！可是old h1 expire是在新单位h1b被批准的时候吗？
-No. It is when you leave or the I-94 expires.
新的批下来后，可以一两个月后开始新工作吗？
-Techincally, you need to work for the new employer when the h1 transfer is approved if the new H1 effective date is on/before the approval date. But practically, if the new employer agrees, you may work for him a few weeks later (two months may be too long).
