Unless it has changed, the algorithm still matches teams first (by a rough upper/lower half seeding of the whole tier) and then, for each specific matchup, tries to find a suitable match date.

[...] In season 24 I had like 2 cases where the enemy team had said to put 21 flat and then it resulted on the default time being at 20:30 ( http://etf2l.org/matches/65096/ - http://etf2l.org/matches/64660/ ) Of course just after discussing with them about it with the same exact reason that I stated earlier they were more than fine with scheduling it to 21:15 since they wanted to play good 2 maps before the official. I'm not sure if you're able to see the preferred times that the teams have set back then anymore for the specific weeks, but I'd rather trust on the words that the team leaders had said to me back then than what the system would imply.

I personally haven't ever seen a case like that happen. Normally it should only happen in case the timing of teams' games is 20 and 21 or if there is some specific scenario with the time frames.

There's also an issue (?) with the scheduling bot anyways that defaults matches on 20:30 for some reason when team A has preferred time at 21:15 and team B has it set on 21:00. How does that even make any sense other than piss off the teams who want to play at around 21?