My wife was OFW but no longer and we were married in Hong Kong, as we visit regularly we have some experience of Balikbayan visa, it seems it is down to the individual officer, sometimes they say "rules changed and I get 21 days" sometimes they just stamp it one year and no questions and sometimes they say "how long do want to stay for" so it seems like pot luck, pick an older immigaration officer they seem more sympathetic, make sure your wife does the talking and whatever the result do not get involved just be respectful and polite. The visa extension is 2055 pesos.