
Hi Gabrielle,
The dog should be allowed to enter UK with a reading of 0.5ml/IU, as you quite rightly said it does state equal or greater than.
Where is the dog comming into? one of the ports or the airport?
May be worthwhile giving them a bell just to give them a heads up, even though we know what is required the staff manning don't always.
I have to say I have never had one out off four dogs come back this low, they usually come back around 12.5 ish. :)
Edit to add just taken a look at pups and it does state on the bottome
"
An antibodytitre of 0.5 IU/ml or aboveafter vaccination indicates protection against rabies according to the guidelines of the WHO/OIE"
So should be fine if everything else is in order HTH :)