I have recently retired as a TRI/TRE from a European airline. I was paid the standard annual salary plus an annual addition for TRI and a further addition for TRE. The combined additions came to around €30.000 per annum.
The training increments were paid regardless as to whether I was actually training or not.
I do not like the sound of what they are trying to do to you. The answer is to tell them that you are not interested in training under those terms - it simply is not worth the hassle.