Hi again everyone! I quoted my own post above because I wanted to share an update about it. (If you want to read the whole and very very long post, just click on the up-arrow in the quotation)...
SSS has discontinued the auto-debit method of getting our contributions. We had initially wanted to pursue this method and leave about 3 years' worth of SSS contributions plus the minimum maintaining balance in our local bank accounts because (1) we will not need to rely on relatives here to pay our SSS for us--- spare them the hassle, and (2) the auto-debit activity will prevent bank account dormancy. However, since SSS has now adopted a new system of collection, our only remaining options were to have our relatives pay for us or remit from Canada (which of course entails fees and deductions). So we chose the former and our sister was thankfully willing to do the task regularly for us. On the matter of bank dormancy, we decided to still keep the pre-determined 3-year SSS + minimum maintaining and do online transfers to our sibling's account to prevent dormancy. We'll replenish the funds in our local bank every few years by wire-transfer to our own accounts, which also prevents dormancy.
Again, sorry for the long post. I like sharing things that I am learning. Kind of like the see one, do one, teach one approach... I do hope this helps and please share if you have any other ideas and tips!