Just noticed you can see the account’s creation date in flowlab profiles
Grazer: Wed Jul 27th, 2011
Me: Sun May 12th, 2013 (this was my first account, grazer renamed it though)
Mhx Ar: Thu Oct 3rd, 2013
CBG: Fri May 30th, 2014
PixelPizza: Fri Oct 3rd, 2014 (first account)
Luminous: Mon Jul 4th, 2016