The NUJ described the move as a “huge blow to quality journalism” and called on the company to enter talks on the way forward.
It is now in discussions with individual NUJ chapels at the titles affected.
Chris Morley, Northern and Midlands organiser, said: “There is great shock at the timing of this announcement, although our members had been fearful something like this was not far away.
“This is a huge blow, not just in the numbers of people who may lose their jobs but also to quality journalism.
“The two daily papers in Wolverhampton and Shropshire have been the lonely standard bearers for same-day regional newspaper news and sport and had been very successful in that over many years.
“But repeated deep cuts to editorial numbers have critically weakened what they have been able to offer readers by badly overstretching staff.
“The NUJ calls on the company to open talks with unions to find a sustainable way forward. This must be done in a way staff are reassured that directors will not take the discredited path to a cycle of cuts to the core business and then more cuts that drives away still yet more readers and advertisers.
“Any change from same-day publication will require major changes to the way staff work. If the proposals are to be implemented, to work they need to be with the agreement of staff – not by the company putting a gun to employees’ heads.”
There will now be a 45-day consultation period on the company’s proposals.