Just make sure you don't dart The Defeater (if it works) until the rework is done, or you'll lose the title and have to re-obtain it.
But of course
You won't get the title if you dart the last phase. You can dart intermediate phases.
Source: I actually do hardmode.
best drops (reasonably accurate/up to date): 1x Elysian Sigil (LS), 1x Arcane Sigil (cs), 4x Armadyl Hilt (solo at 100m, 100m, 50m, and 5m), 2x Saradomin Hilt (solo at 25m), 5x Draconic Visage (34m,1.2m,1.2m) and various cs/ls/ffa Nex splits.
Drygore Drops: 7 Longswords, 3 Maces, 3 Rapiers, 3 Off-hand Rapiers, 5 Off-hand Maces, 3 Off-hand Longswords
ROTS Shields: 12 Seismics: 16
Ascension Crossbows: 6 Spider Legs: 10
Countless Armadyl armour pieces, Saradomin amulets, Dragon Hatchets, and Fremenik Rings.
Range~Herblore~Construction~Constitution~Defence~Farming~Magic~Attack~Prayer~Strength~Summoning~Slayer~Mining~Dungeoneering~Firemaking~Agility~Magic Mastery~Summoning Mastery~Cooking~Smithing~Fletching~Thieving~Hunter~Woodcutting~Fishing~Runecrafting