Timer for reconnection to old channel

From Huawei document:

Counter: CM33

After the MS seizes the TCH, the BSC sends the HO CMD to the MS. During the handover process, this measurement provides the number of times that the timer for the target cell waiting for the handover completion expires if the MS fails to access the new channel at the radio interface, or the number of times when the timer for the originating cell waiting for the handover completion expires if the MS fails to return to the original channel.

Which timer is this?