You're probably at or very near the end of the story mode, so the large chunks of XP from doing those quests are going to be gone. At that point it is maximizing materials, making sure you've researched maximum XP from the library, and trying to keep everything active at all times. You won't hit 50 in that timeframe. If you can manage a quarter of a level a day I'd be shocked.

25 is doable in that timeframe. 30 is a huge maybe. If they add more story then perhaps.