Does a tortfeasor’s ignorance or mistake as to the extent of damages delay time for a claim against him?

The defendants refer to Peixeiro v. Haberman, [1977] 3 S.C.R. 549 (SCC), at para. 18: “At common law, ignorance or mistake as to the extent of damages does not delay time under a limitation period. The exact extent of the loss of the plaintiff need not be known for the cause of action to accrue. Once the plaintiff knows that some damage has occurred and has identified the tortfeasor, the cause of action has accrued. Neither the extent of damage nor the type of damage need to be known. To hold otherwise would inject too much uncertainty into cases where the full scope of the damages may not be ascertained for an extended time beyond the general limitation period.”