Hi,

This is simple:

1- Export 12 word recovery phrase from your current Blockchain.info Bitcoin (BTC) wallet A
(which did have some BTC on August 1!)

2- Create a new Blockchain.info Bitcoin (BTC) wallet B

3- Transfer ALL bitcoin from Bitcoin (BTC) wallet A to B
Wait for minimal of 2 confirmations! Your wallet A is now EMPTY.

4- Create Bitcoin Cash (BCH) wallet at BTC.COM

5- Import the bitcoin cash with 12 word recovery phrase from wallet A (bullet 1)
(no risk for your bitcoin, since your wallet A is now empty and your bitcoin now is in wallet B)