4 months window of re- entry visa validity?

[Filipinay]

hi everyone! opinions are greatly appreciated. here's my dilemma, im going back home this August for a month to attend a family matter.. my passport and multiple re- entry visa both expires in January 2014..and i wont be able to renew my OWP just yet coz it expires in January as well..now, my question is: should i renew my passport and apply for a re- entry visa and as to my understanding, they give you re-entry visa according to the date of the validity of your work permit, hence my OWP and re entry visa expires in JAnuary 2014 respectively..so, from the time that i get back here in September, i still have 4 months window of validity on 3 of them..is it a safe buffer? pls help, your opinion matters thank u