Holy shit!
Sounds like you’re on track with your training.
When is the swim? If you can, try to get in some open water somewhere. I usually travel for my open water events early so I can get a feel for the water a day or two ahead of time. The water has a different feel to me…
And was this in the 50m Commonwealth Pool in Manchester? If so, I’ve swum there. But the moveable floor was broken, so the pool was set up as 25m. After that, I just swam at my hotel (the Hilton Deansgate, only a 20m pool and warm, but much more convenient, and I liked the glass floor).
@Reece
I normally swim in Salford Quays on a Sunday for open water training. I used to swim at the Y club, but the pool was only 18m 
not that great for long distance.
Mal said:
@Reece
I normally swim in Salford Quays on a Sunday for open water training. I used to swim at the Y club, but the pool was only 18m
Yeah, I had to do lots of turns in that Hilton pool too… and I just counted the lengths then figured out the distance after; it was before I had a watch for swimming. Good luck with your training and with the event!