I saw this on X, formerly Twitter, which says that Northern and TPE now have a reciprocal agreement to issue penalty fares. I'm not sure whether this is new to the forum members, but as it seems to be new and of interest I thought I would highlight it.
(Link and image is to a post from a senior reporter at the Bolton News which seems to show an internal briefing document for staff which explains that a reciprocal agreement between the two companies has been put in place.)
x.com

(Link and image is to a post from a senior reporter at the Bolton News which seems to show an internal briefing document for staff which explains that a reciprocal agreement between the two companies has been put in place.)
x.com
