Game Times and Leagues

What time do games sim?
Each country sims at a specific time. Round 1 games are always 3 hours before Round 2 games. All times are EDT/EST.
08 AM - 11 AM: Japan
09 AM - 12 PM: Australia
11 AM - 02 PM: United Kingdom
01 PM - 04 PM: Dominican Republic
02 PM - 05 PM: Puerto Rico
03 PM - 06 PM: Venezuela
04 PM - 07 PM: United States
05 PM - 08 PM: Cuba
06 PM - 09 PM: Canada
07 PM - 10 PM: Mexico
I want to make changes to my lineup or tactics! How long before a game must I do this?
Games start simming at the times specified above. Each game takes approximately 2 seconds, including data transfers and processing. Basically, as long as you get your changes in before the game starts, they will be used in the game. You are never locked out of making changes to your players or teams except during "Day 101" Rollover Maintenance.
What is the difference between a Major Pro league and a Rookie league, exactly?
The only real difference is in how much they are able to earn and spend. Each league level has an income percentage which tells you how much of the maximum level they are able to earn in ticket sales. Minimum and maximum salaries are modified by the same level.