It is heard very rarely but it is true.
Once I had experienced that out of 4 ticket, 2 were shown confirmed while 2 were there at RAC 1 & 2 in the evening before the journey day. Yet on charting, all 4 were in RAC. But I did not have any proof because 'all RAC' was also a bettered status than what was there at the time of booking (Waitlisted).