Does plan B cover plan C too?

Imaris • Travel Nurse 👩🏻‍⚕️ & 1st time momma 🤱🏻💕

Here’s my friend’s Dilemma:

She and her fiancé are not interested in another child right now; she is in between birth controls and is allergic to latex; she has unprotected sex on 12/28/22 and takes plan B on 12/30/22 but then has unprotected sex again 01/01/23, will she need plan B again or will it cover the entire window ? 🥴😩 Thanks in advance