You actually can set your social posts for just one network and customize the content if you want. If you have more than one account connected it will share to all by default but if you click the down arrow where you accounts are listed you can remove some.
Here's an example where I have one post shared to Twitter and one to Linkedin. They are both set for the same date and time.
The red arrow is where you will want to click to remove the additional accounts. Just use the plus sign to the right of that to add a new post!
Hope this helps,
... View more