We are seeing the same issue. Some builds appear, some don't, some next day, some take days. No email. Apple must be having issues and I hope they are looking into it.

We are having this issue too the last week or so. It's taking some builds a day and a half to two days to appear, and some never appear, with virtually no difference between them. There's no notification emails being sent of any issues. If anyone has any clues as to what is going on, it's much appreciated. I wish once xcode shows it as uploaded, that they would be more transparent about status at this phase

We are having the same issue. No email notifications of any problems. Inconsistent results from build uploads.