Dependent Visa

You are asking this question one day before their travel, really?

Grace period is usually when the permit has expired or been cancelled.  If that is the case then no they cannot travel.

However, LMRA site shows grace period before expiry so if they are travelling on 30th and the visa stamped on the passport shows 1st Sep, then yes they can enter Bahrain on 30th.

But since 1st is a Saturday, the permit WILL expire on the weekend.  I assume that they are linked to your work permit which means that your permit will also expire on 1st.  You need to have your sponsor file an application in the system immediately as they land so that it is lodged before expiry or apply for extension.  Once expired, the permit cannot be renewed and you have to issue new ones and pay again.

Thank You Sir. Yes in the Passport it is stamped expiry date as 1st of September. That means they can enter. Right ?

Sir,
My Visa will expire on 1st of November only.

They can enter.  If yours is expiring on 1st Nov then why is their visa expiring on 1st Sep?  are they on someone else's sponsorship?

No, they are under my Visa only

Then you need to check as the expiry date is the same between a work permit and the associated dependent visa.  It is never different unless you applied for a shorter term visa for them.