Hi everyone, thank you all for your good wishes, I really appreciate it. Poppy had a good night, and seems fine today - a little subdued and tired, but that's not surprising really. She's just out with OH for a little walk. You will be glad to know it has not affected her appetite!
I did speak to the vet yesterday, and we agreed that unless she has any more seizures it is not worth bringing her in, as we have done countless tests on her in the past that were all inconclusive. OH did go to the vet to get a refill of the diazepam suppositories in case she has another fit. Frighteningly, the vet gave me her mobile number with the instructions that if Poppy gets into a long seizure that doesn't stop, that we should call her immediately and she would meet us at the surgery or come to our home, day or night, with emergency medication to inject to stop the seizure. Hopefully we will never need to call her for that.
Otherwise, it's just the same as before - note when and where the seizure happened and any possible triggers. Keep her under close observation and don't leave her alone for the next 48 hours. Start the clock again from now.