Free to watch Movies added to playlist refer me to Sky store when I try to playback later. Why?

[Jim+Main]

Can anyone explain this for me please? When I  see a some movies listed in the TV guide that are free to watch at the time of broadcast but I can't watch it at the broadcast time and want to watch it later I add it to my playlist. However when I go to watch it I'm directed to that movie in the Sky store to buy or rent? 
This does not happen with all movies and has only recently started happening at all.

An example is that I added " Back to the future" which I can watch from my playlist but when I added "The Time Machine" and tried to watch it a few days after broadcast I was directed to the Sky store. Both movies were free to watch in my comprehensive Sky package.

it is really frustrating to settle down to watch a "recorded" or "Saved" movie only to find it's not available. Thanks for any info.

[mikealanr]

@Jim+Main 

It's because glass and Stream doesnt record. Some programming gets clouded recorded, but others the playlist just acts as a pointer to the service which has the on demand / streaming rights for the content. Broadcast and on demand rights can be held by different parties.

Some times older content has more than one rights holder, and you may see a play on xxx button underneath.

MikeAlanR