I'm just speculating based on the transfer rumors. Whether it will actually happen or not is another thing. Hell, Courtois might even up end up staying!
If Courtois leaves and we replace him with Butland, then we have an extra foreign space. Plus, there's also Zappacosta who has been linked with Inter Milan.
Oh we might have alternatives but it's a whole other question whether this incompetent board can pull off the deal. Might end up with Jack Rodwell on deadline day!