How to (when) discard changes on an opened observer

[jacargentina]

I have an observer on object X (opened and listening...), then i need to populate some properties (let say 5 props), but i dont want to react on those 5 changes; then i need to start listening again.

AFAIK, I cant open, "suspend", and then "restart" an observer, right? So i'm thinking on using the discardChanges API. My doubt is, which changes i'm in control of? What is the "micro-task" thing?

My doubt is: my 5 properties population would take 1, or more "micro-tasks" ??