If they took bidline away, would that mean junior trash would get a better rostering experience than they have today? What is the likely outcome of all this and what would that look like for all?
Nobody can really say, since firstly they do not have a crystal ball, and secondly "better" is subjective.
However, under the current arrangements, the "junior trash" (as you call them) tend to work to a "blindline". In essence that means little choice in the work, but due to the vagaries of the system, they work less - by say 10%-15%. So anybody with evening classes on Tues/Wed/Thurs evening is pretty well OK to attend
Unfortunately, this "anomaly" has been noted by the grown-ups, and used as an illustration of how the current system is "not working". It is hard to disagree
One possible outcome might be to leave the current system as far as possible, but find ways to get the Blindlines to near 100% work.
Were that to succeed, not only would there be little choice, and working every weekend, but the mid-week evening classes might not be so safe
That is but one possibility / interpretation, it's a big unknown for all right now...