Can a plaintiff amend its Statement of Claim on the eve of trial?

Counsel for the defendants also argues that the plaintiff had access to the Monitor since commencing this action, and that permitting the plaintiff to amend its Statement of Claim at this late date as the result of a witness statement obtained by the plaintiff only in or about February of 2009 would prejudice the administration of justice and that the amendment should be denied for this reason. He refers me to Behm v. Armitage, 1990 CanLII 6776 (ON SC), [1990] O.J. 162 (S.C.J.) at para. 23. In that case, leave to amend on the eve if trial was denied because the plaintiff had the information necessitating an amendment and sat on it for 27 months and it was found that to grant the amendment would prejudice the administration of justice.