Methods and apparatus are presented for dynamically controlling the re-transmission scheme of acknowledgment signals. A source transmits a first data packet over a slot s1. If channel conditions are favorable, source transmits a second data packet over slot s2, which precedes the reception of any acknowledgment signals. A destination receives first data packet over slot d1 and second data packet over slot d2. Destination decodes first data packet during slots d2 and d3, and second data packet over slots d3 and d4. Destination transmits an acknowledgment signal (ACK1) associated with first data packet during slot d4. Rather then transmitting the second ACK1 associated with first data packet over slot d5, destination preempts this slot with an acknowledgment signal ACK2, which is associated with second data packet transmitted by source. Hence, destination is configured to overwrite the repetition of a previous acknowledgment in order to transmit a new acknowledgment.