My own personal thoughts are needing to find a new supplier for tallow is not enough justification for changing the formula for a popular soap.Or when an owner, in this case, Graham Robinson, passes away, and functional control of Mitchell's Wool Fat Ltd. is passed on to his children. His wife retains controlling interest in the firm, but as she's in her 80's, I doubt she's involved in the day to day running of MWF.
You simply find another supplier for the ingredient you need. I find it difficult to believe that they did not have more than one supplier for tallow.
Most companies have two or three suppliers for ingredients in case they have a problem with a supplier.
It just likely to me that they reformulated to eliminate more expensive harder to supply ingredients to increase profits. they used this as justification as they know it won’t be liked by the customers base.
The other part I don’t like is switching to cheaper ingredients but charging the same price. Just trying to increase your margins when you already have a profitable product. These kind decisions based on making more money rarely work out in the long run.