Adnan Limited $($AL$)$ is a supplier of machinery and spare parts. The machines supplied are installed by AL$.$ Following transactions took place in the last week of the accounting year i$.$e $30$ June $2015$ :

i$.$ A machine was delivered to a customer. The invoiced amount was Rs$\mathrm{.}500$; $000.$ In accordance with the Operating manual, the customer had to arrange a voltage stabilizer before connecting the machine to the power supply. The machine became operational on $1$ July $2015.$

ii$.$ A specialized machine was sold to Sun Technologies $($ST$)$ for Rs$.800,000.$ ST agrees to make the payment on $7$ July $2015.$ However, ST informed AL that it would accept the delivery in the month of august $2015.$

Required:

Applying the principles of IAS $18,$ explain when revenue from the sale of the above machines may be recorded.