In the last hour the the RMT has done exactly what everyone knew they were going to do: announced a 24 hour tube strike over New Year's eve.
The argument reaches back to last Christmas when the union brokered a deal with Transport for London which effectively gave them a 35 hour working week.
What's the problem with that then? Well the RMT now claims that their bosses have made "back-door attempts to displace hundreds of safety-critical station staff under spurious cover" of that deal.
RMT have denied that any job cuts have been made at all.
If the strike goes ahead RMT headquarters will shut down for Christmas at 5pm on Friday and reopen on 1 January.