Emailed Arriva on the 3rd of September. Received a reply today, not a response to my email, but to tell me it's been logged, and they'll endeavour to get back to me within 10 working days...

So that's 20 (or 14 "working") days to get an acknowledgement, with an expectation of up to another 14 (or 10 "working") days for a response.. if it arrives then.. 

So all in all, and I'm going to have waited a grand total of 34 (or 24 "working") days for a response to a fairly simple issue. Really is unacceptable to wait such a length of time in this day and age.