Can I actually make progress with 20 minutes a day?

I work 60 hours a week and only have a tiny window to study Bulgarian before bed. Everyone says you need immersion, but that’s impossible for me. I’m trying to move away from gamified apps and get more actionable output. If I use Chickytutor.com for 15 minutes of structured correction daily, is that enough to see actual movement in my fluency, or am I kidding myself?