Alternative role is identical to 'redundant' role; short deadline for decision

My friend has been told that her job role is redundant, but that she can apply (alongside others) for a newly created alternative role.

What we find suspicious is that the new job is identical; 70% of the responsibilities listed are in her current role's job description, and the remaining 30% are duties she already carries out, at her manager's request. The hours and location are the same. Only her job title and salary would change.

Is this allowed? My understanding is that for a job role to be made redundant it has to literally BE redundant, i.e. the position is no longer required. How can that be the case if an identical new job role is being created to replace the 'redundant' one? This just looks like a sneaky way of cutting her salary!

Also, she's been told in her first consultancy meeting that she must decide within 3 days whether to apply for the new role. However, not all of her questions from that meeting have been answered. She's been told she'll have the answers 'within 3 days'! Is that not unfair? In particular, our understanding is that the consultancy period must last more than 30 days if more then 20 people are being made redundant, which is the case here.

Finally, is this new position considered 'suitable alternative employment', and if so is she entitled to a 4 week trial?