In reply to Michael Hood:
Warning: zero direct knowledge speculation starts here
Talking to people who've done the route it's a hard one to grade. It sounds like it's French 7c, with reasonable, but not perfect protection, which is a bit fiddly to place. If it were easy to read, and secure climbing, this would put in in tough E6 territory.
Since it's a tough one to onsight it deserves the upgrade to E7. As you say, the difficulty of on sighting it would mean pure "onsight" E8 grade might be justified, but this just feels wrong based upon a gut 'how prepared would I be to try the route' feeling.
What an amazing year Emma is having - it seems like she's put in top end and memorable performances in almost every climbing style this year. Maybe someone should give her some axes for the winter?