Why the SDLP could waver as welfare reform D-Day looms in Northern Ireland
Tomorrow is D-Day for welfare reform - although Northern Ireland's politicians are notorious for breaking deadlines.
Some have suggested Stormont is doomed - and while it may well be true, it will take a little longer to play out.
There is also the possibility that one of the parties involved, most likely the SDLP or Government, will weaken a little under the potential threat to devolution.
At the moment the DUP has tabled a motion to extend UK-wide welfare reforms here.
It proposes allowing the Executive to top up payments for three years by cutting other budgets.
Sinn Fein agreed to this in the Stormont House Agreement (SHA) - but then said it believed there had been an open-ended commitment to help all claimants indefinitely.
If the reforms are not passed then a massive Civil Service redundancy scheme may fall.
Paying for it depends on loans from London, which are conditional on balancing the books on welfare.
Losing these loans by ditching the SHA would also mean the end of plans to cut corporation tax to 12.5%. Tomorrow's vote may not go ahead.
Both the SDLP and Sinn Fein have tabled petitions of concern, which can halt or delay the Bill unless a majority of nationalists as well as unionists back it.
However, MLAs from both nationalist parties would need to support the same petition to do that.
Today Deputy First Minister Martin McGuinness argues that welfare reforms cannot be imposed on the most vulnerable and the DUP is "responding to pressure from the Tories in London."
He points out that Sinn Fein got more votes than the Tories in Northern Ireland, something unlikely to persuade the party that won the United Kingdom general election.
London says it intends allowing civil servants to set Stormont's budgets. That would bring about cuts across departments - as well as the likely resignation of one or more of the big parties. That prospect would put further pressure on London to act.
The other prospect is that the SDLP may get something that enables it to withdraw its petition. It has put a number of proposals to the Secretary of State and sources say some are cost-free.