Avatar metioned this in wilders "Check for update period is 12 hours now. It was 6 hours earlier but we've decided to increase it.Number of active users (and servers load too) increases rather fast"
http://www.wilderssecurity.com/threads/adguard-for-firefox-open-beta-test.364186/page-2#post-2387398
http://www.wilderssecurity.com/threads/adguard-for-firefox-open-beta-test.364186/page-2#post-2387398