Yes, well ... the English language is not my strong point, especially when rushed. I'm linguistically challenged, I'm an American

"When to blood test
Each UK rabies vaccine manufacturer advises in its datasheet for the vaccine the best time for a blood sample to be taken after the vaccination. Make sure that your vet gives you a signed record of the date the blood sample was taken with the microchip number clearly stated.
and"If your pet's blood test is satisfactory, you should ask a vet (in Great Britain a Local Veterinary Inspector) to issue you with an EU pet passport. You will not be able to bring your pet into the UK under the Scheme until 6 calendar months have passed from the date that the blood sample was taken that gave a satisfactory result."
All explained here:
http://www.defra.gov.uk/animalh/quarantine/pets/procedures/support-info/blood.htm