The reason I think personally, that supercell changed the walls from blue to red is for the next update (Halloween) in October. Hopefully we will be seeing a blue town hall 11. In the past supercell has taunted us by providing on what a th 11 could look like. I think the extra 25 walls would also be used for th 11.
Why you shouldn't dismiss the town hall 11 idea? Well because there has been town hall 10 for about 3 years now. Every day there are new maxed town hall 10's. Supercell will have to do something eventually. So why not now?
Clash on folks

