Well, the statutory bill of rights are just like any other law. They don't have any special way of changing and making amendments (unlike the constitution which has the referendum process to follow). The statutory bill of rights would be amended in the same way that, for example, The Road Safety Act would be changed - it would be taken through parliament or changed in the courts. But, for the entrenched rights the public must vote on it.
This way you could argue that the entrenched rights are more fair and just as we have a say, where we don't have as much a say with statutory bill of rights.
In my textbook it sets out the difference between australia's rights (entrenched bill of rights) and the united kingdom's rights (statutory bill of rights)
Differences
United kingdom:Statutory rights (a bill of rights) listed in the act of parliament --
Australia: No bill of rights
United kingdom: No constitutional entrenched rights --
Australia: Five constitutional entrenched rights
United kingdom:Many rights protected --
Australia: Only five protected under the constitution.
United kingdom: An act of parliament can be passed to amend the Human Rights Act if it can be seen publicly safe -- Australia: Rights can only be removed from the Constitution through referendumIf it is in your textbook you should read about how things work in the united kingdom, that would help make more sense.