Get a gym membership for shower usage just in case. There are many things that can balloon the project, father in law and I did his over a couple weeks, I wouldn’t put a "solid weekend"timeline on things. If it’s your only bathroom, be prepared for alternative showers, but it is definitely something a layman should be able to do.

How far into the earth is it going?

If you’re pulling it out and putting it back in any appreciable distance, it’s probably already plugged. Also if it comes out without unscrewing it might just be a marker. What does the in ground end of the pipe look like? Is it threaded? It could be someone is just having a laugh…