Pretty sure the UK licence is good for 90 days .. No idea why the rental place wouldnt accept it..Perhaps like a lot of local policemen they simply are not aware of the law!
Personally I would not drive here on my UK licence, especially in large cities like Manila and Cebu..
As a foreigner its not unusual in Manila to have your licence confiscated and used as a bribe chip..
One of our tenants,a Canadian now uses online fake international licenses for when he`s in town..They look so convincing these days that the local cops dont seem to have a clue.. He lost two genuine International licences due to local Police..
There are some pretty good British and international ones with holgrams available for around 15.00 20.00 Quid...
http://fakeidentification.co.uk/fake...tification.php
Not that I`d suggest anyone actually try to use one here...God forbid!!

You can convert your Brit licence to a Filipino one in less than a day but bare in mind that you must renew every year.. Non renewed licences are subject to a penalty each year..