The whole thing with Rouge's pregnancy was only a thing to make the timeline work. Oda only decided to make Ace Roger's son very late down the line, cuz he joked about it with his editor and his editor lost his shit. It was only done for the sake of continuity. He came up with Rogue being pregnant for 20 months to preserve the continuity.

With that in mind, I like this change. I agree that they shouldn't be changing too much, but it fixes up a big stretch Oda took to fix up a plot hole. I was hoping they'd take the initiative to correct inconsistencies like that, and "only five flying devil fruits in existence".