Update 2:
So, the car was repaired to excellent standard as per the last update. A few weeks after I had the car back, I phoned up my insurance company to see what the status of the claim was. Apparently, the other party was disputing liability for the claim.
Here we go, I thought :/ The other party apparently disputed the claim on the basis that I had failed to indicate. I pretty much laughed down the phone. I did indicate, and even if I hadn't it was a lame defence and doesn't justify driving into someone. My insurer asked me to send over all my photographs so they could fight my case; they agreed liability was clearly with the other party.
I went one step further and not only sent my photos, but a full diagram of the accident, and a written statement of exactly what had happened, time of day, conditions, all that stuff, and sent it off to my insurer so that they can forward it to the claims handler working for the other party's insurance.
Another couple of weeks go by, and I phone up again to check what's happening. "Oh, we have received your statement and photos, but haven't sent them to the other party's insurer yet...we'll do that now". Not sure why the delay, but OK.
Another couple of weeks go by and I phone again. "We are just waiting for the other party to respond. We'll chase them now". Fine.
About a month goes by and I phone again to check what's going on. Claim is still "on-going". I ask how often they chase the other insurer for updates, "Oh, we chase them every two weeks". I ask them to keep my updated as to the progress of the claim and leave it at that.
Another few months go by and I hear nothing. Being busy with work and moving house, I don't bother to chase them up much. About a month ago I ring them again on a Sunday and ask for an update. "We still haven't heard back from the other insurer....I cant ring them now as they will be closed, but I will do so first thing on Monday and give you a call back". Great.
Another month goes by and I've heard nothing - not even a call back to say nothings happened. Last week, I receive a renewal notification, which is due mid September. They've already halved my NCB and added about £300 to my premium, even though the claim was still "Pending".
Not happy, as the last time I phoned I stressed that my renewal was due and I wanted an update on the claim in case it affected that. Phoned them up today and sounded off a bit about the situation. Got promised that the other insurer would be contacted today and I would receive a call back before the end of the day.
Finally got a call back a couple of hours ago. The other insurer has finally realised that despite the protestations of their customer, they don't have a case, and admitted full liability. As a result of me lodging a complaint for the poor response and feedback I've been getting from my own insurer, they are sending me a cheque for the excess + £50 compensation as a gesture of goodwill. They have also notified their renewals team that my full NCB is to be reinstated, so I can phone them up later after getting some comparative quotes and sort out renewal/switching as necessary
Quite a long and drawn out procedure for what should have been a simple case, however I'm pleased with the outcome. I should have claimed directly with the other party's insurer. It would at least mean less hassle with my own insurer come renewal time.
Glad it's sorted now though - lesson definitely learnt.
tl;dr - Other party ended up disputing, claiming I didn't indicate, as though that somehow justifies driving into me. I send off evidence. Insurance companies twiddle their thumbs for nine months before settling in my favour and giving me £50 for not bothering to get back to me. Win.