There are two limits namely TALIM and MAXTA.
Usually we will put TALIM less than MAXTA. Assume TALIM = 10, MAXTA = 12. This means that as soon as limit 10 is reached an emergency handover will be triggered. But if there are no servers etc and the call continues upto 12 TA, it will be dropped.
MAXTA is also the limit used to filter RACH requests and will fail a request if its TA is greater.
It will be a pity if there is no such hard limit for TCH TA call drop in Alcatel. Even Huawei has got one 🙂 But perhaps when optimizers look into starry night for solutions then this happens. 🙂 🙂 🙂