Hi, I have repaired dozens of these with only a front drum replacement with no issues. With only 49,000 miles I would replace the front drum only. Aamco should at least warranty the work that they perform but not the entire transmission. They should warranty the front A drum and the front seal for leakage and that's about all. If they will not even warranty the work that they do I would take the car to a Jaguar specialist or a transmission specialist who is familiar with the A drum failure and who will make the repair for you. I've never had a problem replacing only the A drum on a low mileage transmission. The $1990 price to replace the A drum should also include a fluid and filter change. The price is reasonable for an A drum replacement with fluid and filter.