Car is in workshop - NO COURTESY VEHICLE!

My car - Kia Cerato has been giving me a tough time as the gear change is very rough and jerky. This is extremely unusual as it is an automatic transmission. After over 6 months of having this problem, the workshop finally agreed that they can see what the problem is. The car has been booked in and I was told that there are only 2 courtesy vehicles in the entire dealership and they are both out! This is very hard to believe, but I accepted it, as I was told it would take 1 week to have the problem fixed. I have made a plan to get around with alternate arrangements for 1 and a half weeks. Finally, after contacting them(they dont call me to update me), they tell me that they are still waiting for a report to tell what is wrong with the gearbox! AFTER 2 WEEKS! Nothing has even been diagnosed!! They also say that they can't tell how long it will take as it seems like a bigger job than they thought! How long am I supposed to suffer without a car??? Kia Centurion needs to get me a courtesy car ASAP! And make an effort to inform the client of the progress of their vehicle while they have it!