TCP per se doesn't allow for situations where if I know that packet A with an update U1 to a structure S hasn't yet reached the destination - then I would like

TCP per se doesn't allow for situations where if I know that packet A with an update U1 to a structure S hasn't yet reached the destination - then I would like to automatically discard A with U1 and send a packet B with update U2. Essentially the issue with TCP is that it's based on queues, rather than having a callback that could simply poll the applicatio:n "hey - I couldn't yet send that data - do you have an update so that I could retry with the fresh one?"