If she lives in London and close to the studio, I can see that the producers would have have let her move back home without much conflict. They got the footage they needed of all the contestants oohing about the big mansion. This isn't Big Brother - the kind of 'at home' footage is used less and less these days, and I'm betting Lauren and her family have given permission for occasional filming at their home anyway.
TBH, I suspect this will work out very well for Lauren - back to home comforts, a place to escape the pressures of the competition, but still close to where she needs to be on a daily basis. She could do very well out of this decision. I doubt she has time to get swept up back into her 'real life'.