Paired formations were originally supposed to permanent, but "by popular demand" I am going introduce a "Split a formation" rule - so it will be possible, but treated as a "Special Action" (see rules p13, col2). A second FAQ document is due on the Wargames illustrated site in the next few days and it will be spelled out there.
There are no penalties for evading archers through a paired unit of Bills or men at arms (rules page 18, bottom of Col1 and top of column 2. Archers in a mixed block are an exception to the usual "evaders are disarrayed" rule.
Rallying off a disarray token takes 1 action, rallying off a daunted token takes 2 actions (FAQ document, page 2, Column 1, 2nd question). Since a unit only has two actions in a turn you should rally off the daunted token first.
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