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
But in a dark winter night Spartacus
broke through the lines of the enemy, and in the spring of 683(28)
was once more in Lucania.
28. That Crassus was invested with the supreme command in 682,
follows from the setting aside of the consuls (Plutarch, Crass.
10); that the winter of 682-683 was spent by the two armies at
the Bruttian wall, follows from the "snowy night" (Plut. l. c).
The laborious work had thus been in vain.
Crassus began to despair of accomplishing his task and demanded
that the senate should for his support recall to Italy the armies
stationed in Macedonia under Marcus Lucullus and in Hither Spain
under Gnaeus Pompeius.