Help with Projections failing after upgrade to 4.1.1

Hi team

I have logged a ticket with EventStore support, but really need help,

We have a projection on a stream that worked fine for a few years now. We have upgraded to 4.1.1 and at first, it worked fine

We have a max age on the stream the projection reads from. yesterday we failed our master node over and we get “'Event number 44733 was expected in the stream {OurStream}, but event number 44773 was received. This may happen if events have been deleted from the beginning of your stream, please reset your projection.”

After talking to the business we have now reset the projection. We waited an hour or so and tried to start the projection again, and it comes up with the same Fault.

This has started to happen in our pre-prod environments first when we logged our ticket on different projections. but now it’s in our prod cluster.

Anyone that can help us out with this?

if support see this here is my ticket number

This is now affecting one of our production applications.