This is not confirmed yet, and certainly not final, but we wanted to keep you all informed of the day-to-day updates in the filming of Order of the Phoenix.
The last report we had told us that all of the young marauders were included in the script. However, we are now getting mixed reports, and the most reliable of them says that nobody has been cast for young Sirius Black or young Remus Lupin, and that their scenes may have been cut.
All that is known for certain is that there is one scene with young James levitating and teasing young Snape while Lily tries to stop him and gets annoyed.
Young Snape has another scene (in flashback with no dialogue) where he sits huddled on the floor with his parents arguing.
There is also a scene that is not from the book where young Snape is talking to young Pettigrew about You-Know-Who.
Of course, it is way too early to know for certain which scenes will be in the final cut of the film. Some may end up on the cutting room floor, and script rewrites are still common. So we may see them cast Lupin and Black yet. However at this point it doesn't look like it.
We will keep you posted as we learn more!
Source:
SnitchSeeker 
Young Lupin and Black dropped from 'Phoenix' film? 
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