If PS4 was narrowly ahead of XBO, XBO was narrowly ahead of Switch, and the total sales between the 3 were 300k, then we're looking at gaps of probably 30k at the most.
So:
PS4: 130k
XBO: 100k
NS: 70k
Even under this extremely conservative estimate for Switch, that would still be a 226% increase over what VGChartz thinks Swtich sold last Black Friday in the UK.
http://www.vgchartz.com/weekly/43065/UK/