Hi Sebastian,
I am quite sure she asked me to just ‘confirm’ my schedule for the interview that has already been conducted!!
I replied to her; yes, I will take part in the interview and told her directly that this is something I never experienced before that HR would ask a candidate to confirm anything backdated.
More strange thing is that, she replied and gave me her personal phone number so that I could call and acquire. I did and she insisted that its their recording system. Sounds so strange for me.
Anyway, I do NOT think I will get the offer since I feel I did not perform well on the interview. So, probably it is really just a strange UN process.