Hi, in everyday conversation, we say ろくじはん、しちじはん、はちじはん.
For the tome of transportations, the workers in the station, airport, etc, they use ろくじさんじゅっぷん、しちじさんじゅっぷん、はちじさんじゅっぷん. There are cases they say さんじっぷん and ななじ. The same happens on the news on TV, radio, etc.
I hope this was helpful.