Arguments::verify_special_jvm_flags is used to check the validity/integrity of the special flags table e.g. to check that obsolete and expired flags get removed in the release they are supposed to. This is called from a gtest. To prevent this validity test from failing as soon as we bump the release value, and to allow a grace period for the actual obsoletion/expiration to take place, we only trigger the failure once we hit a specific build number. This number was initially set at 20 based on the total of 33 builds for JDK 13.

Today we hit build 20 of JDK 15 and there is still an outstanding issue to obsolete the MonitorBound flag - JDK-8230940. As that issue needs a little more time to complete, and because of the noise the test failure causes in the Oracle CI testing framework, the build number will be bumped to 25.