You should never have last minute changes. If you do, that means you didn't plan ahead. If you want to give yourself the best chance of having a successful letter program, look at your program as though you're Andy Rooney sitting in an easy chair and looking for anything to complain about. For decades, the method of choice used by people marketing to consumers has been to perfect a mailing piece and send it one time to as many people as possible. However . . .
People write letters as if they are selling toothpaste or hair dryers to consumers.
However, any letter that requires your reader to think in business terms is actually a business letter. So, if you're promoting a pension, life insurance concept, Roth IRA or long-term care policy, don't think in terms of consumers. Instead, approach your prospects as businesses. Sending a series of letters, all designed to educate your prospects and build your credibility. I call it Wave Marketing.