Just had a look at Championship tables from years gone by on this day (29/10)
If I am being honest - History is really in our favour, most of the sides who have been top on this day of the year in previous years have ended up promoted, most automatically
A few that haven't
Reading were unbeaten and top at this point in the 2020/21 season and they ended up finishing outside the play-offs - Albeit that season was slightly skewed as it started later due to to COVID and they were only 8 games in at this point (We actually were the first team to beat them, 3-2 at St. Ands)
Sheffield United were top at this stage in 2017 and didn't finish in the Top 6
Derby in 2014 lost the play off final
Watford in 2007 lost in the play-offs semis
https://www.11v11.com/league-tables/
If anyone wants to have a play around with the table generator, you can do so on the above link^