From CIN:
Sources also report that TUI is close to ordering ships from STX Finland. While the shipyard was not immediately prepared to comment, it would be a stretch for TUI to commit funds to a newbuilding, considering TUI posted a loss for the first nine months of its fiscal year, and the German market may be approaching a saturation point. Royal Caribbean’s commitment to restoring its credit rating would also restrict its spending, especially in these challenging geopolitical and economic times.
I don’t think they will build. Not with the Celebrity Century still sailing for Celebrity. Remember the other two ships in the TUI/Mein Schiff fleet are both former Celebrity Century class vessels.