I am sorry to hear you risk redundancy, but in answer to your question we have a similar model at my school which has been successful (for the children, I understand it's awful for 1-1 TAs who end up losing their job).
The 1-1 system isn't viable in the current financial climate. The child's funding usually doesn't cover the full wages of a 1-1 TA, meaning the school are running at a deficit and are also able to provide no additional support for that's child in order to meet their needs (such as resources which could help them) as all their funding purely goes on staff wages.
Yes the children do all have differing needs but these are managed by the qualified SEN teacher and the two TAs we have in the unit, same as they would be in a special school. The 1-1 support enables children to remain in a mainstream classroom, but if you take them out of the classroom and teach them in a small hub which caters for their needs, the need for 1-1 lessens.
If children have needs so extreme they require 1-1 even in a small hub, I'd question why they are not already in specialist provision. I know places are in very short supply, but these are the children who absolutely should get them first.
We currently have 8 children in our hub, taught by one teacher and 2 TAs. It's more cost effective than 8 1-1s and enables the children to be more independent while accessing learning appropriate for them.
Obviously schools need to have space for such a facility, but for schools which do have a spare classroom it does make sense.
I sincerely hope you are able to keep your job. If you do, I hope you find the hub system a positive experience and are able to see the benefits.