if you are booking for end to end...it will go into RAC.....it is showing Available 1...but when you book 5 tickets...
1 you will get berth ..1 you will get CNF but berth will be aloted during charting( ex: just like you see just AVAILABLE for 27th march but when you make booking you will only get CNF )
rest 3 will be in RAC...
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more...
as you can see for 3rd april..it has RAC 4...so it will confim 100% ..
without making any delay.. go ahead and book...they will confirm by/on the travel date 100%