Haste makes waste
Please consider that making a good film takes time and plan at least three months ahead.
Planning the shooting can take up to eight weeks. The phase following the shooting, the so called post-production (editing, compositing, grading etc.), may take up to an additional four weeks, depending on the complexity. So, if you need a film in four weeks, you should consider postponing the deadline or to not make a film at all – unless it’s a short outdoor movie with no 3D. If you want something more complex and have little time, the stress on all sides will be great, and the result might be lackluster.
„I’d rather have it right than right now“ is a good motto.
Also, please consider that creating the 3D requires a good amount of time. Even if you have all planning materials ready, creating complex 3D environments can take up to a few months.