Hello, I was looking at the solutions for the piggybacking implementation of Lab3 Q1 and I noticed that something I thought had to be implemented isn't there. So with piggybacking, the piggybacking timer begins when data is received, waiting to see if the ackowledgement frame can be sent in the same frame as the next data frame, which will be sent from the receiver. My understanding was that the piggybacking timer needs to be stopped if piggybacking does in fact occur. Say we have two ends A and B. If B is able to piggyback an acknowledgement onto data it is sending to A, then it is transmitting the current ack_pending value as ack_seq. When A receives this, given that it has received data, it will do ack_pending = f.data_seq (line 134 of the solutions I think) so the ack_pending value changes. If the piggyback timer is not stopped after this happens, it seems that it will still transmit the old acknowledgement frame with the old ack_pending number. (Or maybe instead of stopping the timer we can check if the ack_pending value is the same as the one when the timer began and then transmit the ack frame if the value is the same?) Am I perhaps misunderstanding something in the code or concept of piggybacking, or is this a missing feature?