This formula's own materials state "as low as $1.63/day on the 6-bottle plan" — worth understanding the simple arithmetic behind that specific figure.
$294 total for a 180-day supply works out to $1.63/day, per this formula's own materials — worth confirming that division yourself rather than taking the daily figure at face value.
A per-day cost is easier to compare across package sizes than a lump-sum total — worth calculating the same per-day figure for the 1-bottle and 3-bottle packages yourself before assuming the 6-bottle plan is automatically the better value for your situation.