Have you noticed whether these work dreams feel stressful or more like your brain just... replaying the day? There's a real difference. What's happening is your brain is essentially doing maintenance work - sorting through what matters, strengthening neural pathways around the stuff that's been demanding your attention. When work ramps up in intensity, it naturally takes up more mental real estate, so of course it shows up in dreams. That's not a malfunction, that's your brain doing exactly what it evolved to do.
The tricky part is that this kind of mental processing can feel exhausting even though it's necessary. You're not failing to "switch off" - your mind is still filing away and consolidating everything from those intense work periods. The pattern usually settles down once things calm down at work or your brain figures out a new baseline. If it's been going on for months and it's keeping you from actually feeling rested, that might be worth paying attention to - not as something weird, but as a sign that the intensity isn't really letting up, even when you're technically not working.