There is no particular rank upto which mock allotment is shown it shows allotment upto that rank till which all the seats do not get filled up like josaa will show mock allotment for all obc seats available in all the institutes that are taking admission this year from josaa counselling also mock allotment is not very correct as many people change their choices or do some changes in their preference order so whatever allotment is done in mock allotment it is not very indicative of what you might get in actual rounds.