Catholicism - How can I deal with the possibility of being on call on Sundays?

I work for a large, Fortune 500 company as a software developer. One of the pinch points is that we need to be 'on call' for one week at a time on a rotation and this might include Sundays. We are not paid extra for being on call and the work can be done remotely at home. There is not always work to be done while 'on call'; it's just if there is a severity 2 bug then you will need to be available to investigate the bug. I still attend mass on those days. It's rare that this occurs on Sundays, because most of our customers do not work on Sundays. It would be very inconvenient to change my rotation to exclude Sundays and given that it's rare to be called on Sundays, I'm wondering if this is really an issue from a Catholic perspective? We are not called on Sundays for just any type of bug, but bugs just for things which may take the system down or pose massive security threats. *** **Edit**: For clarity, the software I work on is not being used to support hospitals or emergency services, it's purely for commercial purposes. I have talked to my local priest and he did mention that missing mass and working on a Sunday are two separate concerns as well. He did mention that I could attend a Vigil mass on Saturdays if I cannot attend on a Sunday. He said working on every Sunday is not acceptable but it's not the case for me, it's every 6 weeks at max. I talked to my HR department and they said there is no legal way out of working on Sundays. The local laws apply and the local laws are more in support of employers in this situation and they also mentioned the contract I signed.