As you probably know, Rome was cancelled while they were halfway through filming season 2. Originally, the plan was for season 2 to cover a fairly small amount of time (I think I remember reading somewhere that it was supposed to end with the Battle of Philippi, eventually covered in episode 6, or possibly its immediate aftermath). This would have meant the series never got to cover some of the most famous and most hotly anticipated incidents in this period of history - in particular, Antony and Cleopatra's relationship and their eventual defeat and suicide. Fans of I, Claudius would also have been denied the chance to see the Rome writers' interpretation of one of that series' most famous and colourful characters, Livia.
So, the writers decided to change their plan for the end of the season and speed up the plot. And we're talking F1/Nascar/Moto GP/choose your racing metaphor of choice levels of acceleration here. Episode 7, 'Death Mask', starts sometime after the Battle of Philippi, which was in 43 BC. So it's 42 BC at the latest. By the end of the episode, having entirely omitted Antony and Cleopatra's first relationship, it's at least 40 BC. This episode starts sometime after that and ends in 37 BC, with Antony (re)joining Cleopatra. Episode 9 skips the years 37-32 and starts somewhere around 32 or 31, in the lead-up to the Battle of Actium, and Episode 10 takes place in 31-30, from Actium to Antony and Cleopatra's suicides.