Could be all just pretty pragmatic. Maybe the titles are not definitely deciced, and work is in such early stages that it IS too early for every announcement. Albums HAVE already been shelved, Dylan tours HAVE interrupted, plus press and Media work has to be planned very carefully for the very exact moment and not months before...
If you and your pregnant wife haven't decided yet what name your child will have you won't tell the list of possible names to friends, family or mates. And within the first three months you probably won't even tell it to your Boss or tell us if you expect a boy or a girl...
LE
Actually, my wife
is pregnant!
We're expecting a baby in July, and it's a girl. Her name will be ... ah, you got me on this, I won't tell.
But seriously, even if they don't have a name or the song titles yet, they could just post the occasional pic from the studio (studio diaries, remember them?), tell what they're working on, what guests they have, what gear they experiment with etc. So many artists do that today, and it keeps people interested - until the big day finally arrives.