The quote isn't sourced, but Blogtor Who
is reporting that Jenna-Louise Coleman claims there's a filming gap until series 8. Her reason does make sense of the recent hand-smacking the Benedict Cumberbatch received for saying that there will be a Sherlock
series 4; it could be that Moffat and Gatiss intend to film Sherlock
4 this year as well.
However, it's also an odd quote that's devoid of context, so she may not have meant what the headline claims she meant.