Ok, my understanding was that (again, I’m not lawyer, this is not legal advice!), if there is a two-year home residency requirement on the J-1 holder’s visa, then both J-1 and J-2 holders cannot switch to another visa before you have either (a) resided for two years in the country of residence, or (b) were granted a Section 212(e) waiver approved by USCIS. But perhaps that’s different for some J-1 categories.
