Rahal Letterman Lanigan Racing Pre-Race Notes  REV Group Grand Prix at Road America Round 10 of 17 in the 2019 NTT IndyCar Series  DATE:     June 21-23, 2019 PRACTICE BROADCASTS:     Live on INDYCAR Pass, the direct-to-consumer streaming product from NBC Sports Gold, on Friday from 12:05-12:50 p.m. and 4:00-4:45 p.m.  And Saturday from 12:00-12:45…