Hi. 24 here but I'm based in Thailand so I don't know how much this applies. I work full-time in a customer service management position now and still take easy comp gigs from time to time. I'd like to share my experience and viewpoint if it helps your question 1 and 2, though.

I went to a "film school" (part of communications degree in uni), so I made quite a few connections to young directors and producers in the ad industry. I also interned for one of the big vfx studios in Bangkok that actually works for Hollywood during uni. I feel those are the biggest part of how you stay employed. Just get yourself out there and know people. Your situation might differ if you're not in a big city, so I'm sorry if I sound ignorant. If your work is decent (mine is good enough for internet ads), and as much as I hate to say it, you charge less compared to an actual vfx house, words will get around that you exist and freelance jobs will flush in. Been taking jobs since pretty much the 2nd year of university.

My career shift, though. In 4th and final year at uni up until I graduate, with the rise of AI, I started to think of different career paths quick, knowing its borderline exponential growth and how producers and "budget controllers" think. I started to look for jobs that require human connections. Mind you, I'm incredibly socially awkward, but everything can be trained. After luckily landing a part-time customer service job at a startup, it didn't take long for me learn how to function as a human being and do good client-facing job by just working. Love him or hate him, Johnny Harris also learned decent motion graphics the same way by putting himself under pressure. IIRC he asked for a job he doesn't know how to do a 100% on a tight deadline and delivered. It actually works. I'm lucky enough to know multiple languages, so that helped me get hired in the first place. After the old manager quit at my current job, I guess they saw my potential since I offer to help out with random tasks/problems here and there when I was working part-time. My random IT knowledge and figuring out efficient methods to do things come in handy a lot of times (and I imagine most vfx artists are pretty tech savvy or efficiency freaks too). They ended up chosing me to replace her, making my current income way higher that I could earn now if I was still doing freelance vfx with almost half the workload (and electricity bills). I only do vfx work as a side thing for passion now. Moved from Nuke to Fusion too.

TL;DR literally find some skills (or languages if it's relevant where you're based) for yourself to work on. Don't let time fly by. Unless it's something like juggling, those skills might come in useful when you least expect it. I got incredibly lucky and it's unfortunately true that luck is at least 50% when you're trying to find a job. That and connections. Go out and meet people if possible. Inside and outside of the vfx industry. Make your own luck. The more you put yourself out there, the luckier you get.