Hello, Royhwa!
We would recommend upgrading - SERVER_NAME bug is something that can manifest itself in very unexpected places.
However, it is safe to use RC1 if you deploy your application on the systems that are guaranteed to not have other applications using Cassini installed. But if you release it to customers that can potentially install other programs using Cassini on the same box in the future, then you are getting in the situation where problems are likely.
RC1 does not have any expiration dates built in.
Support of RC1 will be available, but will be limited to issues that we can answer without doing much of research. There will be no new builds of RC1 version.
Best regards,
UltiDev Team.
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