The UK government explicitly lays out a strategy for provate cameras to be bought and operated with mandatory rules for police access to footage. [1]

This is on top of the cameras that ARE owned by government entities - 18+ city councils [2]. And it's expanding [3].

Why do you think it matters if they are linked together? Retaining footage and handing it over to police on request (not warrant) is a requirement. The IPA allows collecting this information in bulk (eg from cctv providers) with warrants. [4]

[1] - PDF Warning https://assets.publishing.service.gov.uk/government/uploads/...

[2] - https://www.bbc.com/news/uk-england-17116526

[3] - https://abcnews.go.com/International/wireStory/uk-funds-stre...

[4] - https://www.legislation.gov.uk/ukpga/2016/25/contents/enacte...