UI: Support different UI modes for live events

I give you an example:
We have a live mpd with total duration of 2 hours. Start the player and wait 1h24m
The total segments stored on server are for 1 hour, the current player time is 1h24, but the user is not able to see segments older than an 1 hour.
User should see the seekbar like this
1h24m |----------------------------------|xxxxxxxxxxxxxxxxxxxxxxxxxxxxx|-------------------------| 2h
.......................segments unavailable...............segments available..........................future segments

In current implementation when moving the scrubber to the beginning it will show to the user the segments 1 hour older. User will be confised because the show started 2 hours ago and it is able to see only segments 1 hour older.

Sample screenshot:
https://drive.google.com/file/d/0B_ElWh6cyPN0S0hQaGRWcjFOclk/view?usp=sharing

iOS dash player have this implementation support