MyCarCheck Incorect Mileage or Clocked?

Hi guys, really need some help here.

im in the process of selling my much loved mini Cooper

i agreed a price with someone only for him to inform me that he thinks the car have been clocked. this was a shock to me and filled me with dread. after calming down a bit i decided to investigate into this and found the info mycarcheck gave me was very confusing.

my car was registered on 01/09/2004. i checked the vosa website and tracked the mot records back to its first mot on 07/05/2008 with the milage of 14,000 and the mileage climb seems fine every year.

this is where the confusion comes in, according to MyCarCheck the recorded mileage on 09/04/2008 was 149,000! (yes correct amount of zeros)

question is can the mileage be recorded before the first MOT?

or

have the mini had an incredibly had 4 year and then been clocked before the first MOT.

the car is in stunning condition and runs beautifully . surely it couldnt have done over 170,000. the clock is reading 68000 and that matches wit MOTS and its service history.

please can someone help me as i believe this is an error on the behalf of MyCarCheck.