From the limited dataset it looks the last digit comes from:
last digit = (<sum of previous the digits> + 2) mod 7
So ticket 98494660 has citation #984,946,605
Ticket 98494661 will have citation #984,946,616
(The example of the pattern mistakenly starts with an citation number #984,946,606 which they said does not exist, rather than #984,946,605 which is the one shown in the image)
So ticket 98494660 has citation #984,946,605
Ticket 98494661 will have citation #984,946,616
(The example of the pattern mistakenly starts with an citation number #984,946,606 which they said does not exist, rather than #984,946,605 which is the one shown in the image)