It starts on Monday evening, and goes on until Friday evening. They all take the day off on Saturday evening, the ruddy slackers and then continue on Sunday evening. There is a omnibus edition at 10.00 on Sunday morning, although the timing on this can be somewhat unreliable if Remembrance Sunday, and other major events get in the way.
I think the answer lies in that each nightly episode is NOT 15 mins long !
It starts at 19:02 or thereabouts, after the 19:00 news bulletin. And if you take off the intro and outro music for each episode, the 6 weekly programs can easily be fitted into the Sunday morning slot.
Hope that makes it all clear...if not...I am here to help !
I always watch the Friday episode on my laptop whenever I remember over the weekend Hopkirk. It took me ages to realise I was missing any and thought my memory was worse than it actually is.
Mikey, myself, Pooka and The Builder all said what you said @ 13.12, at 09.28, 09.59 and 10.06 respectively. Just saying:-)
The Sunday episode has only existed for less than 20 years and was a result of popular request ! And the Friday is repeated, albeit as part of the Sunday morning Omnibus