A surviving Force Z would not immediately reverse every Japanese advance. ABDA would still need most of December to organize, even with Phillips available, so the Philippines probably follows its historical course in this scenario. The main Japanese carrier force also needs to replenish, regroup, and work up after Pearl Harbor, delaying its renewed southern operations until late January. That interval constrains the January reinforcement timetable, while events around Darwin and the Java Sea become more speculative as the counterfactual moves into February.
Notable Point · 56:16-57:43
Why Force Z's survival would not rescue the Philippines
ABDA still needs time to organize, leaving the Philippines exposed even if the later southern campaign changes.