"Subject to Change" Usage

I have the following sentence:

(...) these dates are subject to change.

Should that, instead, read:

(...) these dates may be subject to change.

Are only one of these usages correct? I want it to be interpreted to mean that the dates may change. (but they may not necessarily change)

My guess is that we're working with the following definition of subject (from dictionary.com):

19: (Adjective) open or exposed (usually followed by to): subject to ridicule.

I think that would make the first quote valid. But how about the second?

Solution 1:

Let's start here.

Subject: Likely or prone to be affected by

So, let's see that phrase with the definition instead of the word.

These dates may be prone to changing.

So this means that there is uncertainty as to whether or not the dates could change.

However, the phrase

These dates are subject to change.

Indicates that you know the dates could change, and that they might.