Redundancy of two roles and making a hybrid role foe a new person

Myself and a fellow worker carry out two different roles within our department but can cover during holidays and sickness. We have been asked to reduce our working days from 5 to 3, the alternative is redundancy, well we are going to accept the 3 day week.
Both our salaries are high due to the fall in market rate and that has been mentioned verbally by our employer.

We have asked a number of questions and one related to handover, here is the question and the response from the company.

Question: If outcome is redundancy then who would any handover be made to?

Response: If it is necessary to make both current roles redundant then a new hybrid role would be created to cover a reduced job function. This would be a more junior position than current, and hence, market rate salary of c.30K

Now the function will not change, just they want to role the job into one and save money by recruiting a new person.

Is this legal and surley I would not have anything to hand over as my position is now redundant and as such my work does not exist...

Redundancy isn't just when your work ceases to exist altogether, it's when a requirement for your job ceases or diminishes. Your employer needs to reduce costs, that's what this exercise is about. So it has basically put forward two options, either you and your colleague both reduce hours and salary on a pro rata basis or they combine the duties of both to one more junior role. Clearly the requirement for the type of work you and your colleague do has diminished as they feel they can manage with you both on reduced hours. If your work had ceased to exist altogether you would be redundant without the option to continue on reduced hours.

What they should have done ideally is put forward both options to you and given you both an opportunity to be considered for the new more junior role.