Response time is how long a locksmith takes from receiving the call-out to arriving on site and starting work. It depends on the distance, the traffic, the time of day and the other call-outs coming in at that moment.
An exact arrival time given without knowing where you are is worth little. What is reasonable is an honest estimate based on your location and being told if there is a delay.
To shorten it, give your full address, with the urbanisation, block and number, and send a photo of the door: that way the right tools come along first time. On large urbanisations, also say which entrance to use or give a landmark. We are from Torrevieja and work across la Vega Baja, available 24 hours a day. More under emergencies.