There is probably no illegality. That would be determined by product labeling, product instructions, or a REM being violated. The 1-day vs. 2-day inservice is most likely an SOP (standard operating procedure) put in place to properly educate the office and avoid liability issues to them or SUN. The SOP should be in writing, should be reproducible, and should be followed to the letter or changed properly by SUN in writing. If you are uncomfortable with the situation, by all means report the matter to compliance. You already have the supposed recorded manager quote. Rather than threaten or heighten the situation with the manager, I would ask the manager to clarify how the 1-day rule is mandated. Assuming it is an SOP or handbook suggestion, it should be in writing either way and part of sales training if it is a mandate that affects education, proper product use, legality, patient safety, etc. If you have any discomfort, the matter should be reported to SUN compliance.