Day 1 — arrive and get wet
Land in Tawau by 2.00pm, road transfer to Semporna, afternoon boat across — most travellers step onto the jetty by mid-afternoon. Check in, gear sorted, then the house reef: an orientation dive for divers, or straight into the snorkelling for everyone else. Sunset from the jetty ends every first day here.
Day 2 — the full Mabul day
This is the day the trip is for: a morning-to-afternoon schedule of boat dives on the muck sites, with surface intervals back on the island over lunch. Divers targeting the macro list should brief the guide the night before. As the light drops, the optional add-on that makes the day: the mandarin fish dusk dive, followed by dinner.
Day 3 — exit, done properly
The no-fly rule owns this day: no flying within 24 hours of your last dive. If you fly out of Tawau today, yesterday's dusk dive was your last — this morning is for snorkelling, a village walk, and the boat back to Semporna. Flying tomorrow instead? Then a final morning house-reef dive is on the table. Build the flight first, then the last dive backwards from it.
What this plan trades away
Honestly: Sipadan. Two nights leaves no realistic slot for a permit day — that is exactly what the 4D3N plan exists for. If Sipadan is the point, spend the extra night.
