H4 --> F1 --> H4 COS - Dropbox eligibility

Hello, I had a question regarding my wife’s eligibility for Dropbox, while we travel to India for stamping in Dec 2018. Her last arrival in the US was on H4 visa, in 2016. The H4 visa stamp in her passport expired on 27 Sept 2018.After coming to the US, she did a COS to F1 visa for the purpose of studies. After completing her studies here, she applied for H4 visa again and it got approved till 2021. So currently she is on H4 visa again. I am still with the same employer since the last time my wife entered the US.1) Please let me know if she is eligible for Dropbox, as the last valid stamp in her passport is still for H4 visa.2) If she is eligible, can I include her stamping application along with my Dropbox application OR does she need to submit one separately? Please advise.  Thank you.