[WillPS]

I thought TVam handled all the regional ads from Camden? Or was that just assembly of the tapes ready for playout?

Either way it was something that was pretty quickly ditched in the name of cost saving.

I can't find it now but there was an account of all this from a technician/engineer who was there from almost the start to the infamous lockout...

This one?
tvforum.uk 

Which led to www.dgsys.co.uk  which talks about Knutsford and suggests the bulk of the ad operation for TV-am was done from London and Knutsford was used to "insert" some other stuff as needs be.

But I don't think that's quite what you're referring to, but its related.

Very interesting stuff, thank you for sharing.

No, what I was thinking of was some old Geocities-style webpages where a chap detailed his entire personal experience from joining TVam when they were on the verge of bankruptcy to eventually being locked out.