It may be too late to sue, which implicates the statute of limitations.  Then again, it may be too early to sue,  Why would one bring an action too soon?  The answer is that sometimes time could run out before events can support a legal malpractice case which will mature later.  Here is an example from Law.Com and Gina Passarella atT he Legal Intelligencer
August 02, 2010

"Wolf Block and a number of former partners are seeking a stay of a legal malpractice lawsuit brought against them by car dealership owner Alan Potamkin over the firm’s drafting of a prenuptial agreement.

Potamkin is in the midst of a divorce action in Florida in which the validity of the prenuptial agreement has been brought into question. He entered a tolling agreement with Wolf Block to toll the statute of limitations while his attorneys as well as lawyers for Wolf Block attempted to enforce the prenuptial agreement in the divorce action. When the Florida judge denied summary judgment on the issue and ruled discovery of assets should continue, Potamkin filed the complaint in the malpractice case in Philadelphia Common Pleas Court.

Wolf Block, through its attorney, Nicholas M. Centrella of Conrad O’Brien, requested the Philadelphia court issue a stay in the malpractice action until the divorce is finalized.

In denying summary judgment, the Florida court ruled the prenuptial agreement does not conclusively establish that either party waived equitable distribution of the assets. Wolf Block now counters that the Florida ruling was "simply an interlocutory ruling" that denied summary judgment and did not determine the legal effect of the prenuptial agreement.

"At the present time, therefore, plaintiff cannot establish the essential elements of his claims beyond piecemeal allegations of purported damages based on what has transpired thus far in the divorce action," Wolf Block said in its motion. "Until the Florida court enters judgment assessing damages, if any, against plaintiff in the divorce action on the basis of its interpretation of the prenuptial agreement and post-trial remedies are pursued to completion, the scope of plaintiff’s claims and the alleged damages he purportedly suffered will not be known."

Wolf Block said in its motion to stay and supporting brief that it understood Potamkin had to file the suit before the completion of the divorce action because of statute of limitations concerns. But it said the state Supreme Court’s 1993 opinion in Bailey v. Tucker allows for the defense to file preliminary objections and seek a stay, at which point "the trial court shall then reserve its ruling" until resolution of the underlying action"