Question regarding H1B visa. My daughter is on H1b valid up to Sept 2018. The company will apply for extension for another 3 years up to 2021, as I140 is approved in 2015. Suppose the extension is approved by August 2018, she plans to leave the company and join MBA in a US university, in Sept 2018. After completion of studies in about 18 months, can she recapture the balance time up to 2021, if some other company files her H1B. Can they apply in CAP Exempt? Also will her priority date be valid even after the previous company cancels her I140?