The legal malpractice statute of  limitations commences when the mistake is made.  It runs for three years from that date, although it may be tolled by the continuous representation doctrine.  That continuous representation doctrine requires that the attorney and client agree that more work needs to be done, that the attorney continues to work on the case, and that a relationship of trust and confidence ensues.  Here,in Singh v Edelstein  2013 NY Slip Op 01255   Decided on February 27, 2013 Appellate Division, Second Department  it looks like the post-nup agreement was the last act by the defendant, and that plaintiff did not discover the problem until too late.

"To dismiss a complaint pursuant to CPLR 3211(a)(5) on the ground that it is barred by the applicable statute of limitations, a defendant bears the initial burden of establishing, prima facie, that the time in which to sue has expired (see DeStaso v Condon Resnick, LLP, 90 AD3d 809, 812). The statute of limitations for a cause of action sounding in legal malpractice is three years (see Matter of R.M. Kliment & Frances Halsband, Architects [McKinsey & Co., Inc.], 3 NY3d 538). The three-year period of limitations runs from the day of the alleged malpractice (see Alicanti v Bianco, 2 AD3d 373, 374, citing McCoy v Feinman, 99 NY2d 295, 306). The statute of limitations for legal [*2]malpractice may be tolled by the continuous representation doctrine " where there is a mutual understanding of the need for further representation on the specific subject matter underlying the malpractice claim’" (Zorn v Gilbert, 8 NY3d 933, 934, quoting McCoy v Feinman, 99 NY2d at 306).

Here, the defendant met his initial burden by establishing that the alleged malpractice occurred in November 2007, when the postnuptial agreement was executed, and that the action was commenced in August 2011, more than three years thereafter. Accordingly, the burden then shifted to the plaintiff to raise a question of fact as to whether the statute of limitations was tolled or otherwise inapplicable, or whether she actually commenced this action within the applicable limitations period (see Jalayer v Stigliano, 94 AD3d 702, 703; DeStaso v Condon Resnick, LLP, 90 AD3d at 812; Williams v New York City Health & Hosps. Corp., 84 AD3d 1358, 1359; Krichmar v Scher, 82 AD3d 1164, 1165). The plaintiff failed to meet that burden (see Williamson v PricewaterhouseCoopers LLP, 9 NY3d 1, 11; Rodeo Family Enters. LLC v Matte, 99 AD3d 781, 784). "