Cigar or disk hiding in clouds

I was walking my dog on Upper Norwood Recreation Ground, which has a great panoramic view of the sky. While taking in the view, I spotted what I originally thought was an interesting cloud, as it wasn't anything like the cloud formations surrounding it. I took photos and a short video, then walked home. As I walked along the road, 13 minutes later, I looked in the same direction of the weird cloud, and not only was it still in the same place (unlike the clouds surrounding it), and had split into 2. The single and double cigar shapes were similar in colour to the slate grey clouds, mixed with the fluffy white formations, but the shape didn't change like the clouds over time. I've been watching a lot of declassified examples of UFOs and UAPs recently while I work from home (HR Advisor in digital marketing agency), which is why I thought it was particularly odd as it looked just like other sightings shared on TV and online.