Shan-e-Bhopal - तेरी खूबसूरती से नजर नही हटती, नजारे हम क्या देखें - ललितपुरी रेलफैन

I search for berth availability against 'LADIES' quota in 12480/Suryanagari Express and found some interesting result.
For some days it is showing 'Available' and for some days 'Not Available'. Why such inconsistent behaviour?
2013-10-18, Fri NOT Avbl NOT Avbl NOT Avbl 0m old Refresh
2013-10-19, Sat NOT Avbl NOT Avbl NOT Avbl 0m old Refresh
2013-10-20,...
more...

Sun NOT Avbl NOT Avbl NOT Avbl 0m old Refresh
2013-10-21, Mon Avbl 5 NOT Avbl NOT Avbl 0m old Refresh
2013-10-22, Tue Avbl 4 NOT Avbl NOT Avbl 0m old Refresh
2013-10-23, Wed Avbl 5 NOT Avbl NOT Avbl 0m old Refresh
2013-10-24, Thu Avbl 3 NOT Avbl NOT Avbl 0m old Refresh
2013-10-25, Fri NOT Avbl NOT Avbl NOT Avbl 0m old Refresh
2013-10-26, Sat NOT Avbl NOT Avbl NOT Avbl 0m old Refresh