You will loose the capability to ground the secondary at the center of the Wye. This is likely a big problem unless you want to float the secondary or have some other exotic mean of grounding. In most country, floating the secondary can only be done using special protections and considerations.
I would probably return the transformer and insist to get it fixed. They simply have to re-wind the coils.
Experienced is earned, common sense is taught, both are rare essentials of life.