Do not have anything important sent to you via post office....for starters, it takes up 6-8 weeks (if ever) to receive mail from other countries, AND the postal system in the Philippines is very corrupt, I have had mail ripped open (they are looking to steal money that might be enclosed). I would try to set up online banking options for your bank statements.
All of the above applies but if I can add that it can helpful to have an additional mailing address in UK with friends/ family who can open letters and email or call you with the information. We are now registered to pay UK tax on line but to do so we needed a one time access code that was valid for 10 days. They mailed it to friends who then wats apped the code to me. Same has happened with new bank cards that arrived here but had an acivation code coming under a second letter but had to be used within 10 days. I got it redirected to our pre registered secondary address with friends in UK and it worked. Banks in UK have been understanding, tax and pensions office not so helpful when you explain delays. Proof of life request was 10 weeks getting here but we were fore warned by someone on this site and knew exactly what to do. Thanks who ever did that it was great info.