public void deleteMinimumVersion() throws IOException {
		synchronized (syncObject) {
			if (minVersion == currentVersion) {
				throw new IOException("Unable to delete last remaining version");
			}

			// Rename previous version/change files
			File versionFile = bfMgr.getVersionFile(minVersion);
			File changeFile = bfMgr.getChangeDataFile(minVersion);
			File delVersionFile =
				new File(versionFile.getParentFile(), versionFile.getName() + ".delete");
			File delChangeFile =
				new File(changeFile.getParentFile(), changeFile.getName() + ".delete");
			delVersionFile.delete();
			delChangeFile.delete();

			if (!versionFile.renameTo(delVersionFile)) {
				throw new FileInUseException("Version " + minVersion + " is in use");
			}
			else if (!changeFile.renameTo(delChangeFile)) {
				delVersionFile.renameTo(versionFile);
				throw new FileInUseException("Version " + minVersion + " is in use");
			}

			// Complete removal
			delVersionFile.delete();
			delChangeFile.delete();
			int deletedVersion = minVersion++;
			verDBListener.versionDeleted(deletedVersion);
		}
	}
Delete oldest version.
@throws IOException if an error occurs or this is the only version.
Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/store/db/VersionedDatabase.java