Haven't done this in awhile. I last broke 1,000 miles in December of last year, but did it in 27 rides instead of a foolhardy 22-- that's a 45.6 miles per ride average.
Also, the Rapha Festive falls in there in December-- where I have to do +300 miles in 7 days.
A thousand in December is significantly easier than a thousand in July, I can tell you that for absolute certain. I think I had 2 rides for the entire month start after 7am, and one of 'em almost killed me.
Will he take it easier in August? Who knows!