HANG ON!!
Haha... There could be invites sent out this Tuesday for a digital event at Apple next week to announce the new machines! They could then be released this month! At this point it's looking extremely likely we'll get new kit this year.
Of course, if TranceX only wants or needs a 13inch and it sounds like they can get one for free (?? Not sure I understand the money side of the situation), then that is the reason to go for the deal. Guessing they may not be released until next year based on zero intel isn't a good reason when all the rumors point to an event in October and a release date this year.
If TranceX really wants to get new kit, but this offer has tempted them, then that's a tough choice. Does TranceX need a bigger screen etc? We don't really know enough info.
I'd recommend TranceX to wait at the very least until Tuesday this week to see if there is any movement at the station.