As an update, I am now in Samui. I came on the 16th and am here till the 26th with my immigration appointment at CW on the 23rd (under consideration, report back on 23rd). I didn't get any home visit before I left and my wife's niece is staying in our house while we're away and there has been no visit, so I guess there won't be one as my appointment is on Tuesday.
I did check with my friend who has a contact at CW and they said there is an investigation team and they usually do home visits. Whether my documents and history (28 years in Thailand and always squeaky clean but usually on non B extensions based on employment, this is my first non O extension application) means they don't need a home visit, who knows.....unless there is one planned for Monday.
Anyway, I am leaving my family here to enjoy the holiday, flying back on 23rd morning to meet my appointment at CW then flying back here in the evening. Question: I forgot to pack long trousers. Is this an issue? I will wear smart shorts, trainers, and a polo shirt. I have searched but get mixed information. Does anyone know? I still have time to go and buy a pair of jeans or trousers if need be.