See for yourself. The first direct Blackburn to Manchester service on a Saturday is the 0719, arriving 0832. No sign of an 0627 on a Saturday. However, the 0729 is faster, arriving 0826 and is cheaper as the "Via Bromley Cross" ticket is valid.
If you need to arrive in Manchester before that, there is the 0612, arriving (at Picadilly) 0756 with a change at Preston requiring the more expensive "Via Preston" ticket.
There's also an 0655-0824 option requiring split tickets and a change at Hebden Bridge showing on NRE which is probably not worth it for the sake of 2 minutes.