Upvote:2
Luckily, Heathrow's website has an excellent tool to take the guess work out of this.
I used March 9 as your travel date, flight AC888 from Ottawa and BA157 to Kuwait.
As per the website, you'll have to:
Its been a long time since I've been through Heathrow so I cannot comment on the rest areas, but from what I know there are individual seating pods and lots of seating areas that you can avail.
You will not need to re-check your bags.