Steam Sale Dates Leaked?

A post on reddit claims to reveal the start dates for the upcoming Steam sales for Halloween, Black Friday, and their big Winter sale. The post is actually removed, as reddit cites one of their rules, saying this is "unverified," as there's "no mention of a source." Eurogamer follows up on these dates, saying they have "independently corroborated them as correct." However, their post does have the same faults as the original from reddit, as it does not mention a source, so on some level seems likewise unverified. But it does seem like it's been a long time since Steam held a big sale where the date didn't leak in advance, so there's that. Here are the dates for which they are vouching:
The remaining Steam sales in 2017 are:

  • Steam Halloween Sale: Thursday 26th October to Wednesday 1st November
  • Steam Black Friday Sale: Wednesday 22nd November to Tuesday 28th
  • Steam Winter Sale: Thursday 21st December to Thursday 4th January 2018