Dear, I also own an Altis 1.6. After introduction of immobilizer, I was also tempted into exchanging mine with a new one with immobilizer. Called a few dealerships to get quote about my car. As usual, I was quoted 1-1.5 lac below market price with the promise that I would be given delivery of brand new Altis 1.6 within 45 days, if I opted to exchange my car with Toyota sure car exchange program. That 45-days delivery period commitment given by dealership on phone seemed a bit fishy as Altis 1.6 enjoyed 4 months delivery period in the least. I wrote an email to the dealership confirming if the car would really be delivered to me within 45-days if I opted for Toyota Sure car exchange program and I am yet to get any confirmation IN WRITING from their side.
So, better stay away from these stealerships and try selling your car in open market. They may take your car at 1-1.5 lac below market price but would not deliver you the brand new car within 30-45 days period especially if its a GLI or Altis 1.6.