I like Peter quoting the OT Prophet Joel in Acts 2 as a sign of the times.
For me, there is no doubt that the signs of the time indicate we are there.
But knowing where we are just further emphasises the importance of following Jesus’s teachings. Focus on God, not what time it is.
Peter in Acts 2 is talking about the Church of the Pentecost that was formed then. And the destruction of the temple in 69 AD leading to the explosive growth of Christianity - by 60 AD you already had Thomas teaching in India, Bartholomew in Britain and others in Ethiopia, in Central Asia etc.