Not saying these things are definite, just rumours that I've heard from people who're not known to simply make stuff up.
We have been pretty good at keeping our cards close to our chest, transfer wise. But not always down to the club if stories leak out. Agents, players, players' friends, how these things have always leaked out...
Being honest, the centre back story is the one I put most stock in given the lack of detail. When rumours that have been doing the rounds turn out to be true, it tends to be the "heard we're bringing a winger in from down south" vague types of rumour...