I know this is a old post but might help with your Octavia in future..... mine is a 51 plate 1.8Turbo VRS, I noticed a blue sealant on the sump plug and knew there was something wrong here, and surprise surprise some ***K had mashed the threads up previously so the next guy gets to pay for there Elephant like touch!! Up shot of this is I've decided to pay £40 for a Engineering firm near me in Sheffield to Helicoil it , as a new Sump from Skoda is £90 plus there magic sump sealant at only £21 ?? What!!! lol Crazy money!!
Anyway I have my answer I was looking for,and, that it's not just my car with this fault.
And to say it's got full service history ?
And this my fellow people is why I never ever if I can help it take my car or motorbike to a garage..........