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Brit just left her attorney Laura Wasser's office in Century City (she's shown here earlier, with Jayden). And this, after Alli gave her testimony on Monday and Lynne and daddy Jamie have recently given their depositions ... what's up?

We hear Lynne Spears is putting increasing pressure on Britney, through Kevin. In fact, it's looking like Brit's mom is the one responsible for Kevin seeking full custody in the first place. This is what we're hearing, y'all! ... Pix and video of Britney today coming a bit later ...