Skills Assessment and DIAC no. of years exp. should be same?

Hey Guys,

I am confused whether professional years calculation is being done by DIAC itself or its totally based on ACS (Australian Computer Society) letter?

Actually, I got positive assessment from ACS in June 2011 and that time my experience was 5. 10 years as ICT Business Analyst. Now, my experience is 7.6 years and still working on same Job with same company.

I want to apply for ACS re-validation but have a confusion here. As per my knowledge, ACS will give me SAME letter (with 5. 10 years experience) just with extended expiry date. If I submit that letter for EOI (after completing my 8 years job), will DIAC consider my 8 years service (considering old ACS letter with 5.10 years + current reference letter) OR they will consider that ACS letter that will be stating 5.10 years?

Please help

Thanks.