You didn't write about your OS, I suspect you are using a Windows, probably Windows 7. In this case, my answer is:
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Theoretically, not. What you are hit, it is one of the most important problems of the OSes and Windows7 can solve that relatively easily. Different devices and their configuration / reconfiguration should be done independently.
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Practically, yes, but not very badly. It is not clear, what is running on your PLC controller, but considering that you are controlling it from a windows, I am sure, it is not really critical. A little bit of delay could happen.
- There could be another danger, if your next system configuration causes some unneeded interaction between your network interfaces. For example, if your new IP is an IP on your PLC-side network. But it is in most cases some buggy configuration and I susepct you know what are you doing.