Originally Posted by
Dave Noble
There is nothing in the EU regulation that treats a downgrade in advance as any different to one on the day. For most routes where US sells tickets , such consumer protection will not be offered.
Even US carriers are required to comply with EU261 for flights departing from the EU
Read the regulation ( link provided above ) and can decide for yourself what the legal rights are. If you want to believe that there is no consumer protection, it is your choice
In other words, you're unwilling or (more likely) unable to present one anecdote supporting your read of the law. You may wish to begin using "in theory" when posting such advice.
OP: Please report back on how this is settled. I really hope you're made whole, but I'd be shocked if you get 75% of the entire cost of your itinerary back.