The New Sharkster: I play in the same region as you and have led two teams to the nationals (2010 in 8-ball, 2011 in 9-ball).
A) the LO won't change player skill levels
B) the paperwork you fill out at the end of LTC (assuming you won and make it to Nationals) is basically garbage. The first thing you will do as team captain at Rivera is sign in the team and get the registration packet. This will include... GASP..... Filling out the same paperwork you filled out at the end of LTC which asks you to certify your player skill levels.
C) Just fill out the paperwork at Rivera with the most recent skill levels of your players, IRRESPECTIVE of what they were ranked during LTC or a month prior.
D) If a player was a 4 the week prior to nationals, but a 3 at LTC you better put them down as a 4, because after the first match when they run the paperwork through the system all the ranks will be updated and that will have cost you one of your available three rank changes.
E) it's not really that big of a deal, just be honest. My teams have had a total of two rank changes combined in two years of nationals, including making it to 17th place in 9-ball, 2011. In the round of 34 (2011) we played against a team that had FOUR players on the watch list including a skill level 3 female player who signed up as skill level 1. She bumped to a 4 after our match (she was a solid 4, why they signed her up as a 1 is beyond me). There were five formal complaints made against that team (including the monetary deposit to make a formal complaint) and that team was disqualified after beating us by 1 point. Every player was banned and security escorted them out.
Long story short, don't worry about it, the LO won't do anything crazy, just play your players at their ranks and (yes) hold them back to get into LTC, but assume that it will make your first few rounds easy, but the last few rounds more difficult. *or* have them play and get used to being the higher rank and experience with the more difficult matches (my preference).