No mention of a lottery yet, but the general sale for G7 in October is listed now in eplus.
Event: Ｇ７ ＲＯＣＫ☆ＳＨＯＷ 忘れ歌を、届けにきました。
Location: Okinawa Music Town Hall
Ticket sale: 10/14/2017 @ 10:00
The general lottery for tour tickets started yesterday and runs into the first week of March. If you don’t have tickets yet, this may be the last chance before the general sale!