i asuume your eb2 based priority date is more than a year old, plus the avg processing time of 485, so you wouldn't be significantly affected by the upcoming retrogression.
that's why i said your eb2 485 is similar to family 485, as far as your gc is concerned.
after you get eb gc, it would take 5 years for you to get citizenship, while it would only take 3 year for fb gc.