Should UE wait for contention timer expiry and then transmit preamble? When UE is in RRC_CONNECTED state and after transmitting a RRCConnectionReconfigurationComplete message for a handover without dedicated preamble eNB does not schedule any PDCCH transmission addressed to UE C-RNTI before Contention resolution timer expiry and configured to not transmit RLC ACK for this transmission.
But AMpollretransmit timer is expired before contention timer, which initiates preamble for retransmission of RLC PDU whose ACK is not received.