Just after Prime Minister's Questions the bill to reform the House of Lords will be introduced.
And that will make some of the Tory MPs very unhappy.
The plan is that the Lords will be mostly elected from 2015 and it will be reduced in size.
The Government is clear, despite this being a Lib Dem favourite, that this is now a Government bill and they expect it to become law.
But many Tory MPs are determined to vote against it.
And the threat is there: if any ministerial aides don't back it they will be sacked. Some are already saying if that's the case, then so be it.
All three parties back Lords reform, but that doesn't mean it's not going to get bogged down in Parliament.
Tory backbenchers, fresh from their success over the fuel U-turn (and the pasty and charity and caravan U-turns), will no doubt be thinking that sometimes it's better to oppose the Government and, like yesterday, be proved to be ahead of the game.
It used to be rare to hear dissenting voices. Now it seems the Tory backbenches just can't stop.