I have re-sodded in May, February and July and they all seemed to work just fine. The May project I started in early April and finished up first week in May. To me, it has always been about the rain and current weather.
I have established new lawns in December and July, both with success.
But, put me in the category of folks who prefer cooler months than hotter. Less water and less stress when establishing a lawn that is dormant seems to be a lot easier.
we did october with great success in houston..st augustine
also, how are you going to kill what's there now? with chemical do you need to allow time for residual? or going to scrap away top layer and bring in new fill?
Doesn't glyphosate become inert rather quickly (days)? I would think you could spray, till/scrape, and lay sod within a relatively short period of time.