咁呢一段又點解?

8.
Saving of rights
Nothing in section 6 or 7 shall be taken—
(a)
to prevent either party to a contract of employment from waiving, at the time notice is required to be given for the purposes of section 6(2), (3) or (3A), his right to notice or to payment in lieu of notice; (Amended 48 of 1984 s. 5)
(b)
to affect the right of a party to a contract of employment to terminate the contract without notice or payment in lieu under section 9, 10 or 11(2).

咁係咪話俾人炒可以放棄通知期?