Possible Bug in iOS 8 via Streaming iTunes Video results in lost storage space?

Question

Hi looking for suggestions or help on this issue if you can.
I'm not sure if the issue is my attempting to stream a movie from iTunes under iOS 8 or if it is a result of the iOS 8 update (size) itself or some type of memory leak or inability of memory to be released back to the OS.
This AM I had ~4.8GB of free space on my 16GB iPhone 5C; running under iOS 7. I then updated to iOS 8 by connecting the phone to my iMac and doing the install through iTunes under a USB wired connection. I however I did NOT check after the update how much space was "Available" after the update on the iPhone itself.
While streaming a long movie (LOTR extended) from the iCloud through the Apple Video app; now under iOS 8, I received a notification that my Storage space was nearly used up. While looking in Settings\Usage\Storage I can see that I had roughly 250MB of space "Available" but only 12.7GB was "USED." Here is were things get strange. Looking into the "Manage Storage" section I added up all of the space "used" by the apps listed (Video app was NOT listed) and came up with a sum of 6GB of used space. Now why is that? The listed 12.7GB of used space is not equal to 6GB what is using up the remaining 6.7GB?
Now my research of the web suggests iOS 7 was ~3.5GB in size and my best GUESS at iOS 8 is that it is a16GB - 12.7GB = 3.3GB; although I thought iOS 8 was going to use up more space? For the sake of argument lets say iOS 8 is 5.8GB and my calculated Used Space it 6GB, that equals 11.8GB. Where are the remaining 4.2GB?
Keep in mind I added No new apps (albeit a few updates to FindMyFrieds, Remote, Pages, AirPort Utility, FindMyiPhone all to be iOS 8 compatable).  I also force quit the VIDEO app thinking that the video that was streaming was taking up local storage while it was playing. Is it possible that the memory was used up by the stream and is not being Released; hence it seems I have no available space?
Powering the phone down and re-starting it did not seem to do anything.
I still need to go home, connect to iTunes and double check if the available space on the phone matches to what iTunes see.
Thanks and sorry for the long question, just wanted to get as many variables out there in case anyone else has had this issue.

Answer 1

searching.4.answers . . . sounds like you too were able to "inform" your device that the content is no longer needed, great.  I posted a solution that later didn't work for me when I streamed another video (see my post dated Nov 1 - cjdmedia).  I then had great success using what others in this forum have suggested . . . I downloaded the free ibrowse app (do a quick google search for this and you'll find the website for it).  Sure enough it was a piece of cake to navigate to the iCloud assets folder and find and delete the video file.  That is my solution from now on.  Unfortunate that I need to do that to have my storage space clear. 
Also in my post I shared that I thought this was a bug, unfortunately I now believe that this could be intended behavior.  The only question is how long does this data just sit there until it is removed by the system? or is it removed by the system?  If it is not removed by the system at some point then a strong argument could be made that this is a bug. Streaming means that data is not permenantly saved on the device, right?  
My fundamental issue is that I have 16GB storage that really means I have a total of 12.8GB (so says my iPhone).  With no personal photos or videos, only 300MB of music, some books etc, and all the apps I want installed on my iPhone I end up with only 9GB available for anything else.  A typical movie in HD takes up half of that.  Not aware that the data of movies was being stored on my phone while streaming I completely filled up my iPhone only days after completely wiping and setting up.  When I got the notification that my phone was full when trying to take video of my kids Trick-or-Treating - I was infuriated that something was hogging the memory in my phone, perhaps I had upgraded to iOS 8 too early before known issues were eliminated.  I thought I had 9GB of space for pictures and video!  To be fair, Apple did not ruin Halloween because my wife had her iPhone.  I also know that this "issue" has been around since iOS 7 (based on my searching) and I haven't seen any confirmation it has ever been dealt with.  From another apple discussion forum stream itunes purchased movies to iPad I discovered that if your device is almost full you can still "stream" because somehow the system knows how much space you have and then behaves more like what you'd expect from streaming which is interesting. 
So to wrap this long post . . . it is obvious that to stream there needs to be data stored locally, but it is unclear how much data and how long this data will stay on your device.  The quickest solution (requires a computer) is to use the iBrowse app and manually delete the movie files in the iCloud assets folder.