Rugby train station parking

[ian_uk1975]

Just moved to the area and commuting from Rugby to Euston daily. Purchased my season ticket yesterday and asked the guy at the ticket office when (approximately) car park #1 fills-up; he said around 7:30am. Well, I got there this morning at 7am and it was full. Drove to car park #3 and even that was looking quite full already... but I did get a space on level 2. Trouble is, it's a little bit of a trek from CP3 to the platform. So, can anyone advise what time I'd need to get to CP1 in order to stand a good chance of getting a space?

Thanks.