Yes! This is a really interesting and possibly problematic change. I’ve made some speculation, but be warned that there is mention of some ASoS & Season 4 spoilers below.
Obviously the timelines of the series and the books have been shifted around quite a bit. In ASoS, Jaime and Brienne arrive in King’s Landing after the Purple Wedding and after Sansa has departed with Littlefinger for the Eyrie. Of course in the show, Sansa is still in King’s Landing when they arrive, leaving the possibility open that Brienne will see Sansa and maybe even interact with her.
Many fans are speculating that the Purple Wedding will occur in episode 2 of Season 4, since GRRM is writing that episode. So while it doesn’t seem like Sansa and Brienne will both be in KL for long, they will still overlap for almost 2 full episodes.
One way that they would possibly be prevented from interacting would be if Brienne is arrested for killing Renly (as she is in ASoS). However, this is unlikely since show!Loras doesn’t seem to blame her for Renly’s death.
I think it would be really interesting for Sansa and Brienne to see each other before Sansa departs King’s Landing. In fact, it would make it all the more heartbreaking for her to leave KL with Littlefinger not knowing that Brienne has been tasked with finding her (and could keep her safe without any ulterior motive). She would really be in a much better position with Brienne than with Littlefinger, making it more frustrating that she wouldn’t know about Brienne’s oath before leaving. It would also certainly make Brienne’s search more harrowing, knowing that the girl she had sworn to find was so close, and then got away. It really seems like just the kind of dramatic and frustrating thing that GRRM (and the show writers) love!