The abs on combo eq has crept up over the years to a point where in many cases it was not very different from abs, which leads to a world where abs is de-valued. So it has been lowered back to a more reasonable level. We want combo to be worse stats-wise than the pure setups, since it offers some of the value of both.
In most cases it's just the abs% that has been touched, but in some cases a few of the other stats were slightly altered as well, mostly to reduce the defense provided.
I've also adjusted the -db/pb stats on a few abs pieces (notably ebony greaves) to prevent them from becoming attractive for heavy combo. I've made sure the overall pb level of abs is unchanged -- things have just shifted around.
For currently in-game eq and logged in players, the changes will be live as of your next rent or the next reboot, whichever comes first.