Embassy hours are 9 am - 12am, all depends. The internet advertised times are wrong and there is a notice hanging on the gate with times although that is nor always correct either. I went there four times once it was closed even though it was advertised as open.
did it all myself in Bangkok at the big office at Lak Si. Take all the documents and wife take it stage by stage. Slightly drawn out but if I can do it anyone can, I'm useless at paperwork.