The American Airlines Arena has just added Brock Lesnar to their website for the 7/30 show in Miami, Florida. This would be Lesnar's first appearance on WWE TV since the Greatest Royal Rumble show in late April. It would be his first appearance on weekly television since the Raw before WrestleMania.
Roman Reigns will take on Bobby Lashley this Monday night on Raw to determine Lesnar's challenger for the Universal Championship at SummerSlam so Lesnar will know who will be his opponent by the time he appears on Raw on 7/30.
As of now, Lesnar is not being advertised for any other shows before SummerSlam but that could change. He is also advertised for the Raw after SummerSlam at the Barclays Center.
After that, the belief is that he will take more time off to train for his return to UFC. His fight will take place sometime in early 2019, possibly late January. The Raw after SummerSlam show could be his last WWE appearance if he doesn't sign a new deal.