Hi,
With help of basis team, make the proper connections between ECC prod to ECC Dev and BW prod to BW dev.
once connections are in place, better to move objects as per particular data flow.
Example:
1. First move ecc prod data source to ecc dev.
2. replicate ecc dev data source bw dev.
3. move bw prod data active data source to bw dev.
4. later you can move whole connected data flow. from rsa1--> transport connections collect the particular data source data flow.
5. like that way you can do remaining all data flows one by one. so that it might be easy move transports without any issues.
Thanks