Judging by the plenary agenda link that Joe C provided, it seems they're booked next week from Monday to Thursday, and then have nothing planned until the Nov 13th.
At the very least there's a factual error in there. It should read the 13th rather than the 14th.
Further, the MEPs could arguably sit at some point by the end of the month to get this passed -- and I'd wager will, if British MPs pass Johnson's bill.
That said, even if British MPs do pass the bill, I wouldn't be the slightest bit surprised if MEPs end up looking into the text several days later. Insofar as their reputation goes and insofar as I've seen from watching anecdotal debates, MEPs tend to come very well prepared to debates. Given this, I'd suggest they'd be rather unimpressed with a third party sticking a gun to their faces and trying to get them to vote under pressure. So much so, in fact, that I could totally imagine Verhofstadt pushing to get some kind of language in the coming extension so that, if they're not done deciding themselves, it kicks in even if British MPs end up passing Johnson's deal at the last minute.
On the flip side, you can safely bet that MEPs as a group are well prepared for the coming bill already, and continuing to prepare. This has a long history in fact. Barnier has been explaining what his team has been doing every single week since the whole thing began, and their negotiation strategy was out in the open for everyone to read. As such, and in stark contrast with British MPs, who had no idea of what was going on or of what was heading their way until the last minute agreement was passed, with only a few days to go through the thing and conduct an analysis of whether they like it, MEP aides who were following the topic had, if not the word for word legalese, at least a fairly good idea of what was heading their way already.
(Just to be clear, no one is expecting that MEPs passing the Johnson deal will be anything other than a formality. I'm merely suggesting that they will do their due diligence regardless.)
Edit: I reached out to the Guardian article's author for further thoughts. He's suggesting that MEPs won't sit again after the 24th, but didn't say why. Will update this if/when he does.
He also suggested in a prior article that the EU would accept an extension if asked, and apparently Johnson will send a letter to that effect tonight.