Questions about system connections

Would someone help me clarify something?

When the ECC QAS system has been copied from the PRD system, the connection between the ECC QAS and the BID system is broken. I was told by Basis that after the copy, the connection has to be restored, and for some reason restoring the connection between the QAS and the BID system, the InfoSources and their transfer rules are completely wipe out from the system.

We are using the business contents and have not yet did the migration.

I am not sure why restoring the connection between the ECC and BID system would cause the InfoSources to de deleted. Has anyone come across this problem? Is it something that Basis can prevent from happening? I have not seen this from BW 3.5.