^ I know that. Hence why I said I hope it doesn't contradict the continuity by showing the episodes out of order.
Stana tweeted after the news came out that chronology will be off.
There is a simple fix to that. Record them both and then watch them in order the following week.
It was a good ep, hard to tell if Kate's misgivings are a result of what happens in 'Still' but I don't think so as she seemed perfectly happy at the start. I think they were brought about by the questions Vaughn asked her, the ones she has avoided asking herself.
My bet is rather than split them up, the season ends with Castle asking her to marry him.