Signed a contract in February to start at a company in May but haven't talked to them since. Should I just follow up to make sure they haven't forgotten about me?

I worked as an IT intern at a large marketing company last summer part time. They liked me and told me to reach out to them in February about coming back again. I did so February 2nd and the HR director got right back to me saying they would love to have me back, full time even, and sent me a contract to sign that said I start May 9th. Since then I haven't talked to anyone from the company nor my IT boss.

I'm just curious if I should send an email or something to make sure they haven't forgotten about me or anything. Maybe email the HR director asking what time I should be in on my first day? Or should I just not worry about it and wait until May 9th