What was the message your airline received? Cannot find it anymore.
Did it say it closes and ops will relocate to another airport, or did it say that no other airports are found in the area? Since I believe the case is the latter, and correct, since the airport does not relocate but simply closes and in that case automatic relocation does not happen (since the system cannot know what kind of ops you have at the other airport and do you wish to transfer the flights or not, since it may lead to more problems than solutions over there).
Edit. Checked and this is the case. Since there is no new airport opening and no other airport changes at all, an automatic relocation will not happen. So not a bug but intentional to avoid messing your possible other routes/bases.