US Immigration from South Africa

I got NOA after biometrics, for EAD, and still waiting for any signs of life on my EAD card. Anyone else waiting still? Gosh it's taking long!! Im dying to start looking for work!!

I want to preface this by stating that this has nothing to do with my own status. I'm just interested.

A couple of weeks ago there was a thread about a student who was denied access to the US because CBP found texs on his phone showing that he was working with a friend, though he says unpaid. This made me think. What exactly is employment/work? I can think of many grey areas. These are a couple I've thought of:

1. Helping a friend with anything, including things like moving house
2. Volunteering. There is no payment here, but you're working. What happens if you don't get paid but you get a free meal for example?
3. Let's say you're about to go out of status. Can you take paid leave, or unpaid leave? Both you're technically still 'employed'
4. Same as 3, but now let's say you go back to your home country and work remote. You're still 'employed' and paid in the US, but working from another country temporarily.
5. Other way around. You're employed in the UK and travel to the US for a couple of weeks. You go to your companies office in the US to give a 30 minute presentation. That's work right?
6. Actually anytime you go into the US for 'business' is that not work?
7. Let's say I'm a freelancer coder. I have a contract with a UK company. I travel to the US on holiday but need to change something on the website. I log in from the US to make that change. Is this work?
8. Let's say you're out of status, but sell something on ebay. Is this work as you've made money. Does it matter if the item is an old couch, or something original you've made?

I can think of many more situations. What's the general stance here?

I have my Citizenship Interview on Tuesday the 3rd of March, but I am still waiting on my I-751 to be approved. It has been 2 years now, and I will be having my Passport stamped before I leave. What would the chances be of having a dual interview and get this over and done with?

I know it's still a while for me until I get to ROC, but I have no idea how it works.

If anyone would be willing to explain it, I'd appreciate it.

I think ROC is 18months after receiving GC? And is there a 2nd interview, or do you mail it all in?

Thanks!

How long after your interview did you status change online? How long til you got your GC?

Did anyone get any RFE's? My status hasn't changed since my interview yesterday. Waiting (im)patiently.