[Plugin: WordPress Beta Tester] Notices after core upgrade

When I upgrade WP core to new nightly bleeding edge build and reload page, plugin shows following notices:

Notice: Trying to get property of non-object in C:\wordpress29.local\wp-content\plugins\wordpress-beta-tester\wp-beta-tester.php on line 100
Notice: Undefined offset: 1 in C:\wordpress29.local\wp-content\plugins\wordpress-beta-tester\wp-beta-tester.php on line 101

You can open Upgrade tab in Tools menu after upgrading to check this. When you go to dashboard, they are displayed for a while and then disappears.

http://wordpress.org/extend/plugins/wordpress-beta-tester/