Slow Upload Speeds Every Wednesday 3 Weeks in a Row

I've been having trouble with slow upload speeds for 3 weeks in a row now. It happens every Wednesday. I have a 1000mbps plan and get great download speeds. Download speeds are never the issue. Every Wednesday for the past 3 weeks, my upload speeds drop to 0.3 mbps. My wife and I can't upload anything for work and we constantly get kicked out of Teams meetings. Our upload speeds are normally around 35-40mbps. Every Wednesday, I call and they said out technicians who I see are working all over the neighborhood the next day on Thursday. Last week I asked a tech what the problem is, he said "we're getting noise and interference that's affecting your whole neighborhood". They spend all Thursday fixing it and I get normal upload speeds by Thursday evening. This exact same pattern has repeated itself the past 3 Wednesdays. What exactly could the issue be? It's really stressing out me and my wife, we can't upload anything for work and getting booted out of important meetings is not good professionally (we can switch to our phones though to rejoin). Any thoughts? I'm at the point where I want to switch ISP's, but unfortunately the max that other places offer in my area is 100mbps.