Maybe a stupid question, but can I ask how we know they met the 21/7?
https://www.tumblr.com/hoovesandfloorpaws/822822493347807232
Not a stupid question at all! I think there is a lot of assumption from fans here. Things that started as a well-loved fandom theory, that turned into headcanon that turned into fact for some people. But the truth is that we have no concrete proof that this is the exact day they first met. Nothing is 100% confirmed. What we know for sure is that Harry, Louis, and Zayn all auditioned in Manchester for the X Factor in front of the judges and made it through to bootcamp on July 10, 2010. The bootcamp week itself began on July 18, 2010. As we all know, on July 23rd the boys were put together as a group, One Direction was born, and the rest is history. We do not have definitive dates for when and what events took place; we can rely almost exclusively on the aired episodes, what is shown to us, and a few other details. Naturally, many things remain unknown, which can obviously lead to confusion regarding the dates themselves. However, by looking at the period between July 18 and July 23, 2010, we can state with absolute certainty that Harry and Louis met for the first time during that timeframe. Let me also add that on July 22nd (the last day of bootcamp) Louis posted this photo.
Later on, we got this photo, in which he’s wearing the exact same outfit.
In the 1D book "Dare to Dream", released in September 2011, Louis recounted wanting to take a picture with Harry because he knew he was going to become famous. And here we have another fandom headcanon, as it is widely accepted as fact that this is the first photo of the two of them together. Could it date back to the day of the audition, given the clothes Louis is wearing? Personally, I don't think so, because -as mentioned earlier- we know Harry auditioned on the same day as Louis, and there are photos/footage of him wearing a different outfit than the one in the photo with Louis. It is more likely a photo taken during the bootcamp week. However, we don't know if it really is their first photo together. But it is the very first picture we have of them together posing for the camera. And we certainly don't know if it was taken when they first met (when they met in the X Factor toilet), nor, consequently, if it dates back to July 21st.
Another photo that helps us trace the timeline of those days was also released later and shows the boys posing together as a group for the very first time. As we can see, the photo has the caption "1 Direction." Harry is wearing the same white T-shirt, and Louis has the exact same outfit on as in the photo where they are together. Again, we don't know exactly when this photo was taken, but we know that July 23rd is the day they were put into a band; a date also confirmed by the message Liam sent his father that day.
It is uncertain whether they had already chosen the name by that day, but a Tumblr post from July 26 confirms the formation of a "New 'Bootcamp' boyband," with "One Direction" appearing among the tags, and using a photo taken by Louis' mother, Johannah.
So, to recap, we do not know beyond a shadow of a doubt whether their first meeting and interaction in the X Factor toilets took place on July 21, but we can state with near-absolute certainty that it occurred sometime between the 18th and the 22nd.
