It's an odd and specific bug; you'd need to set up silentwhisperer's raid farm design with the redstone timer. Maybe the new design as well?
I've ruled out each and every little detail (pillagers, tridents, redstone) and none of them are the source. And it also only works with raid-spawned mobs. And, when reloading the world, the redstone is shut off. Usually it stays on.
Thank you for your report!
We're actually already tracking this issue at MCPE-94194, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – ✍️ Feedback and Suggestions – 📖 Game Wiki