I have read lot of threads on the topic of Dual/N+1 landscape but out of curiosity posting the question related to transport management.
We are performing EHP8 upgrade next year and plan to use two systems D2 and Q2 as project landscape. Production support is D1 --> Q1 --> P1
When we move transports from D2-> Q2 to D1 (after upgrade), we will collect objects from D2 transports into a new customizing and workbench transport. Technically in D1, I will use SE09 --> create a new transport and include objects using D2 transport and release this new transport to Q1 -> P1
My question is what happens to the D2 transports imported into D1. Do we delete them after creating new transport ? Also, why do we have to collect in a transport in D1? if we don't collect objects in a transport will the objects become inconsistent or corrupted or cannot be modified further ?