FAinbaires
hello,
while am also a wonnabe so my info will be more of advice n not maybe not so accurate but what i would want to urge you for now is to concentrate on the interview preparation.
If you mind will be on the scar,it will distrate you. Go there with a positive mind coz for the last two global assessment days i have gone to, i had doubts about getting the job n my doubts came true so please go with a positive mind!!!
about the medicals, i dont know if they check for scars so maybe some who has gone would shed more light but since its on your upper arm, maybe you're okey.
i wish you all the best and do keep us posted.
~
flyoneday