You can only enter each employee once, though. If you try to enter a single employee more than once, all of your entries for that employee will be canceled. Multiple employers can enter a single employee, however. See the next question for details.
It’s important to note that the extension is activated only when the full application is filed, not when the preliminary registration is filed. Because full H1B applications can’t be filed before April 1, if your OPT expires prior to April 1, you will not be able to get the cap-gap extension. If your OPT expires in early April, you may need to start preparing your full application before you know if you’ve been selected or not in order to be ready to file in time to get the extension.
The other change is the order of the regular and “master’s cap” lotteries. Of the 85,000 H1B slots available every year, 20,000 are reserved for people with advanced degrees from US universities. This 20,000 is referred to as the “master’s cap.” In the past, USCIS would create a pool of all entrants holding advanced degrees from US institutions, select enough to fill the 20,000 spots, and then run the general lottery. The general lottery would include all of the applications entered in the master’s cap but not selected, as well as all of the entries that did not qualify for the master’s cap. This year, in order to increase the percentage of slots going to applicants with advanced degrees, USCIS is reversing the order of these two lotteries. The general lottery including all applicants will first be run, then all unselected applicants who qualify will be entered into the master’s cap lottery.