[Mass Combat] Defensive Bonus in Ambush

[Figleaf23]

Hello All,

On page MC34, it says that in an Ambush:

The ambushers’ commander may select any strategy but a defense strategy on the first round... ambushers receive defensive bonuses, which are normally only allowed for defenses.

However, on MC32 under the Heading Defence Bonus, it says:

A Defense Bonus is a conditional modifier that applies only
during a round of battle on which the side possessing it
chooses a defense strategy (e.g., All-Out Defense). Who gets
this bonus depends on the type of battle:
• In a pitched battle, the side with initiative receives a
Defense Bonus, based on using favorable terrain to anchor
their defense.
• In an encounter battle, a side receives a Defense Bonus
only if they were encamped and hunkered down prior to the
battle (even if they’re confused).

So my question is, based on this information, what Defense Bonus does a successful Ambusher get?