Now is Sky really forefeiting a half hours worth of ad inventory or is it just placed somewhere else?
They can only show 12 minutes of ads in any one hour, and an average of 9 minutes an hour across the day - so they can afford to sacrifice ads in some slots. Sky News at 10 can be ad free but they'll still be 3 breaks in the 10pm hour which on a digital channel can fulfil the maximum of 12 minutes - I think they can show 4m10s of ads in eacch break, though I don't think Sky News take overly long breaks.
Correct - sort of. There ARE three breaks in the 10pm hour - one before the papers at 10:30, one during, and one leading up to the TOTH
at 11pm. That's still one break fewer in the 10pm hour and four breaks in every hour except 10pm.
Now, can I say for certain that there aren't some breaks that are 30 seconds longer than others at some point in the day? No - frankly because I have more important things to think about both as a viewer and as someone who might have to get something on-air right after a break.
The bottom line is it's a break forfeited in primetime when rates would be high, and it's a conscious commercial decision to do so. I've told you (within reason) what I know, so at this point, there's no reason to split hairs any further