勿惊：

What does the Season Pass give me?

The Season Pass can be bought at any time, and will give you any past, and future dlc that fallout 4 releases, including the last 3 dlc's, which are:

Contraptions - Workshop
Contraptions - Vault-Tec
Nuka World

If you own the season pass, you'll have access to all of these, plus:

Wasteland - Workshop
Automatron
Far Harbor

为什么要删掉DLC库内容：

Why were the DLC's removed from the season pass dlc list?

You may have noticed that they were once included a few days ago, but not installed.
They removed it until release due to beta users with the season pass not being able to install their DLC since they already own it.
You'll still get the dlcs once they're released.