It is only on the last day of the season that they do that. There is no other time that all fixtures are played at the same time.
Er.. most rounds see at least 4, games played simultaneously, with a further 2 games back to back, prior/after those games - Broadcasting that in a single 'channel' via tape delay is a nonsense model. It's even worse during midweek rounds, where there are 5 games simultaneously.
Er....that is very much the case, but the only time that they play 10 games simultaneously is the last day of the season.
edit - just seen the original comment said "up to 10 games simultaneously". Meh, my point still stands that the only time all 10 fixtures are at the same time is the last day.