Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
Maintenance of the Burgess-Rights Previously Conferred
In regulating the relations of Italy and of the capital, Sulla--
although he otherwise in general treated as null all state-acts done
during the revolution except in the transaction of current business--
firmly adhered to the principle, which it had laid down, that every
burgess of an Italian community was by that very fact a burgess also
of Rome; the distinctions between burgesses and Italian allies,
between old burgesses with better, and new burgesses with more
restricted, rights, were abolished, and remained so.
In the case
of the freedmen alone the unrestricted right of suffrage was again
withdrawn, and for them the old state of matters was restored.
To the aristocratic ultras this might seem a great concession;
Sulla perceived that it was necessary to wrest these mighty levers
out of the hands of the revolutionary chiefs, and that the rule
of the oligarchy was not materially endangered by increasing
the number of the burgesses.