Despite having a large oak tree in our garden, we’ve never seen one of these before. According to our understanding from the web, its a male Oak Bush Cricket (defined by its long curved cerci rather than an ovipositor). It was inhabiting out kitchen until we were able to capture it and release it back into the oak tree where it scurried upwards relieved, no doubt, to be back in its native environment.
According to the Wildlife Trust its not commonly seen and feeds on smaller invertebrates so something that’s useful.
Always fun to find something new.