Offer means to ask if someone wants something. For example, if I offer you a drink, then I have a drink and am asking if you want it.
So the word offer won't ever mean something you have already.
I further certify that the principal alien is being offered the following position: DOS Notification Date:
This is referring to a new job offer.
What is the difference between; “is offered” and “is being offered”
English tends to use a continuous expression (to be + X-ing) in present tense, where a lot of other languages use simple present tense (like Spanish). Simple present is used to express "repetition", "habit", or "generalization" (reference).
I offer help to those in need - You are describing something you usually do or do all the time.
I am offering help to John - Something that happens once.
“being offered” might mean; it was offered before, and it still is being offered.
If the "reach" back into the past was important for some reason, it would be said just like you did: "still being offered."
This job is being offered to you = I offer this job to you now.
This job is still being offered to you = I offered this job to you in the past and I am continuing to offer it now.