Where would I begin with a complaint about a solicitor?

[YNK]

I'm a upset/concerned about the service I've received during a routine matter (changing a will) and I have no idea who to talk to but it's not something I can ignore.
I don't want to reveal too much info in the circumstances but I have evidence of wrongdoing in letters and although he's aware of my response and offered to talk to his seniors, I've had no response from the firm for a month now.

The legal ombudsman

You need to exhaust the complaints procedure with the firm first. Presumably you still want the work completed to the right standard and the firm should hopefully do that for you. I would also point out, not saying it is the case here, but does happen a lot, when dealing with sensitive matters such as estates and thinking about deaths, sometimes people get upset/take offence when the solicitor is just doing their job/covering things required by their professional rules which may seem unnecessary to the client. Hope you get it sorted. You can also escalate things with the regulator but this takes months and the regulator is pretty useless and you’ll end up having to pay someone else to do the work so I’d concentrate on working with the firm to resolve it.

You will need to fully exhaust the firm’s complaint procedure before you escalate further.

www.lawsociety.org.uk/public/for-public-visitors/using-a-solicitor/complain-about-a-solicitor

The client care letter (also known as an engagement letter) should set out the dispute escalation process. There may be someone senior at the firm as the first port of call, and then other options such as the ombudsman.

Thanks - great info.