I don't understand the oppositions thinking on this general election business. Hear me out before jumping down my throat.
It's now becoming clear what the strategy behind Boris Johnson is, and probably has been since he first became PM. And that is to lead the Tories into a GE asap, and to do so as the champion of the Leave vote. Everything he's done, from the pledges he has made to deprived labour voting area's, the police and the health service, to going to European leaders to get an agreement to relook at the WA based on new and seemingly imaginary alternatives to the backstop, to proroguing parliament to force the opposition to bring the no deal bill through much quicker than they wanted, to getting rid of Tory MPs that voted against Brexit, to proposing a GE to put the Brexit question back to the people.
The opposition abstained, but effectively by doing so, voted down the first govt bill calling for a GE on Oct 14th. I can understand this because the no deal bill hasn't been made law yet. But they have also said they intend to go against the second bill being brought on Monday, by which stage the no deal bill should have been made law. So the statute they need to stop no deal and request an extension is in place. Part of UK law. Fears over Johnson changing the GE date to after October 31st can easily be erased by adding an amendment to the bill saying that the date if the 14th can't be changed.
For me, there is no valid reason for refusing this second GE bill, other than the oppositions desire for Johnson to go to the EU and request an extension. Which he will do. He may be saying now that he won't but that's all part of the plan. He has to go. It's the law. FFS he wants to go. Because it gives him the biggest stage possible to show that this has been forced upon him by Corbyn. Johnson's not bothered about eating humbled pie. He's so thick skinned he doesn't even know what it is.
Have you not noticed how he has been building up the rhetoric with Corbyn. He isn't bothered about SNP or LibDems, or Greens, all of who are much bigger supporters of remain that Corbyn. No, he's going after Corbyn, and it's because he knows that Labour are the most vulnerable with a GE and that they have the most to lose. By making Corbyn the architect of forcing the Brexit extension on him just as he was on the cusp of agreeing a new deal with the EU

. By doing so he is making a direct play for the Brexit voters that dominate over two thirds of labour held seats.
Bottom line here is that Johnson wants to go to the EU to ask for an extension. It is so easy to show the world it has been forced on him against his will, plus will also conveniently sidestep the matter of the backstop proposals. Putting the blame for the extension firmly at the feet of Labour will likely increase the number of Labour voters who will put leave at the top of their voting requirements, and whilst they may not vote Tory many more will probably vote for the BP.