Only the initial consultation where the decision for surgery was initiated by the surgeon-provider is billable. Pre-op evaluations by the surgeon are included in the surgical CPT code and are not billable no matter when they are performed. Adding a modifier 57 is permitted whenever the decision for surgery is made, you should not get a denial for it. It's used for tracking and data mining internally when necessary; the 24-48 is an internal rule some companies have initiated. Here is the CPT Assistant rules that make it clear.
PREOP VISITS – Guidelines **
Source: CPT Assistant MAY 2009 (AMA and CMS)
If the decision for surgery occurs the day of or day before the major procedure and includes preoperative evaluation and management (E/M) services, then this visit is separately reportable. Modifier 57, Decision for Surgery, is appended to the E/M code to indicate this is the decision-making service, not the history and physical (H and P) alone).
If the surgeon sees a patient and makes a decision for surgery and then the patient returns for a visit where the intent of the visit is the preoperative H and P, and this service occurs in the interval between the decision-making visit and the day of surgery, regardless of when the visit occurs (1 day, 3 days, or 2 weeks), the visit is not separately billable as it is included in the surgical package.