unrealised rent from HP

unrealised rent arises in the situation when you give ur property for rent to tenant for his use and such tenant fails to pay the rent amount. In such case property is not vacant.
whereas loss due to property remains vacant means for specified period ur property is not occupied by anyone bcoz of which you won't earn any rental income.
when unrealised rent is received it is treated as gross annual value n from that Standard deduction allowed provided that if you had not included such amount in actual rent received earlier. No question of higher of MAV and FR subject to SR arises

thanks for information