Well,
Their names were written in heaven
Luke 10:20
and when Jesus spoke about the new birth or being born again He said "We are talking about things that we know and which we have seen." So, it sounds like the disciples were born again prior to Pentecost.
BUT
they hadn't spoken in tongues so they became unsaved and unregenerated until they (120 of the 500 disciples) spoke in tongues on Pentecost in Acts chapter 2.