It depends which embassy you are applying to. Some want the 3 months others (defo UK) dont mind if its only been put in same day. As long as the money is in a personal current account in your name.
If you read the comments alot have said it was more likely due to the fact they had the sticker in their passport which were used for the DTVs given at the offices early on compared to the usual stamp that most people are getting.
Theres no real evidence that they were questioning the actual type because they are suspicious of soft power DTVs it could have been coincendental
yes it is after that the flight and accomodation section when you go on continue, before submission. There will be a section to upload financial support and supporting documents
Also you can only upload one document so people are using a pdf tool to merge all the supporting docs together. Most (including myself) used ilovepdf.com
Passport photo and proof of accomodation on first page is jpeg. It then autopopulates the info...definitely double check all the information as it sometimes reads the numbers wrong and people are getting rejected because of that. The next bit after flights and accomodation asks proof of funds and works etc dependent on which route you are applying for. This is where you upload the PDFs
I've spent some considerable time travelling Thailand and never encountered racism or felt threatened in anyway and have many positive interactions with Thai people.