rjd - the Boomers start their training camp about 3 weeks after NBA playoffs are scheduled to end.
After camp they play 5 games in two weeks in South American conditions, with South American crowds. Then they arrive in Rio 4 days before the Olympics start.
I'm not sure what else BA might have been able to squeeze in there for a full strength Boomers' preparation. They presumably felt they needed to factor in time to recover for the likely Boomers' starters playing in the NBA playoffs.
In comparison, USA's full-strength team has teh same number of warm-up games, against similar strength opponent but with a longer break after NBA playoffs. They have a 1 week camp in July, starting 12 days later than the Boomers' camp. Then they play 5 warm-up games against Argentina, China (twice), Venezuela and Nigeria over 10 days. However, all of their preparatory games will be on USA soil with home crowds.