Hi everyone thanks for you replies.
I should add a little more info, I am already back in the Uk as my husbands funeral was on Thursday and i needed to get out of the chaos that was going on there, so am having to do everything from over here now with a neighbour helping me out with the cat side of things over there. I did speak to DEFRA and they gave me the steps of how to do things from over there, they were :
To get the cats Microchipped and up to date Rabies shots.
21 Days after Rabies shot they need blood tests.
After that they need to remain in Canada for 6 months.
During this time i need to ask a vet for a 3rd country official vet certificate but when this is issued it has a 4 month valid date on it.
24-48 hours before the cats fly they need a tic and tape worm treatment.
Once they land in the Uk i can collect them straight from the airport and bring them home with me.
The other option they gave me was to fly the cats here into a secure quarantine cattery and then start the steps from over here. This is the option that is looking more like the one i have to take as i am unable to find somebody to foster them from over here.
I would greatly appreciate being put into contact with anyone who has done these steps already as i would feel a little better hearing personal experiences.
Thanks all