It absolutely matters. Let's say you have a team that's good at 6.83 for whatever reason, they know it in and out, how to draft around it, etc, etc. Lets say (hypothetically of course) that for whatever reason they aren't as strong at drafting for a new patch with minimal time to study it but their opponent is.
If they play on 6.83, they win, if they play on 6.84, they lose.
Now imagine you have two teams with both of these qualities (not playing each other this weekend).
One wins because they played on the familiar patch, the other loses because they had to play on the new patch. The previous team got an unfair win they might not have otherwise have gotten.