The newer masters for the DVDs were carefully IVTCed (and the 29.97 portions brought to 23.976 in I-don’t -know-what-way), and then sped up to 25fps.
Are you sure they did this?
From what I found it was suggested that they used a method called DEFT to convert it to 25 fps. It does produce some combing artifacts but it works 99% of the time and that’s why I haven’t touched the PAL discs since then.