It would seem doing this is pretty straight-forward, you find players of the right level and they are eligible to be rostered. But there are a few gotchas. First, for non-ESL leagues, they will use year-end ratings and you don't know who will be bumped up/down or not yet as ratings don't come out until December. I can help with this through my Estimated Dynamic NTRP Rating Reports that will give you a very good idea on what a player's detailed rating is and if they will be bumped.
But the USTA also has a few extra rules that can come into play, notably around players/teams that go to 2014 Nationals.
There was some angst among some groups of players earlier this year when a new rule regarding the formation of teams with players that had qualified for Nationals in 2013 was put in place. The rule basically said that no more than 3 players that had qualified for any 2013 Nationals could be on a roster of any 2014 team. There was a provision for a team to be able to stay together if they moved up a level as a team though.
One issue many had was that this was too broad, especially around mixed play. Specifically if multiple teams from an area happened to got 2013 Nationals, they were pretty severely handcuffed in how the 2014 teams could be assembled. For example, if a men's 4.0 team and women's 4.0 team both went to Nationals from an area, both with 15 person rosters, and all the players wanted to play 8.0 mixed, the 30 players would have to get distributed across at least 10 teams in order to adhere to the no more than 3 Nationals players per team.
A second issue was that the move-up allowance only applied to the division the team was in. So if a 40 & over 3.5 team went to Nationals, they could move up as a team to 4.0 in the 40 & over division, but no more than 3 of those players could be on an Adult or Mixed team even if they were playing as a 4.0 now. So they would not be able to move-up as an 18 & over 4.0 team.
A third issue was that if a player was simply rostered on the team that went to Nationals, they were subject to these restricts, even if they never played a match at Nationals!
Thankfully the USTA heard the complaints and there have been some changes for 2015. Here is how they have documented the change:
2.06A Move Up/Split Up: Relaxed restrictions for Move Up/Split Up:The first point addresses the second issue I mentioned. As I understand it, the 40 & over 3.5 team that went to Nationals would now be able to play as a team in the 18 & over 4.0 flight.
- Teams are allowed to move up an NTRP team level and play in another age group within the same division
- There is no restriction for crossover between Adult and Mixed Divisions.
- Move Up/Split Up requirements apply only to players who participated in 3 or more matches, excluding defaults, for that team during the championships year.
The second point appears to address the first issue I mentioned.
And the third point sounds like it addresses the third issue, at least sort of. It still doesn't require that a player actually play at Nationals to be restricted, but at least if someone was just rostered or plays fewer than 3 matches they won't be restricted.
The regulation document has the table below listing all the scenarios so take a look at that for more details.