Keeping anything a secret is practically impossible, let alone something like spraying the country with something! The sheer number of people ‘in’ on it would be astronomical and would bound to be leaked, plus those doing the spraying would also be living with family in the same areas they’ve sprayed, so that doesn’t make sense.
However, the photos do look a bloody mess in the sky. I have noticed that same grid pattern and they spread out and turn what was a sunny day in to a hazy day. Whether it’s anything other than water vapour / fumes / pollution i don’t know, but it does look awful.
The MET office do experiment with spraying though, so could it be a case of Chinese whispers?? https://www.metoffice.gov.uk/research/foundation/observational-studies/cloud-physics
That magazine is tremendous!! 😀