From the edge of the forest you can see that there is one heavily armoured figure standing on the tower, and one smaller figure walking around on the deck. The rest is quiet as a mouse.
I think the current plan is to proceed in under the effects of Invisibility Sphere (cast by Syro) which would last for 5 minutes, as well as a scroll of fly per person cast by Syro (only one who can cast spells from arcane scrolls), which also has a duration of 5 minutes. I assume the silence (cast by Trask, 5 minute duration) on Armament will be last, so we can actually cast all the spells Total casting time is 8 rounds, so 42 rounds remaining before whichever spell is cast first ends.
I'm drinking a potion of mage armor (1 hour duration) and casting my scroll of Dragon Skin (50 minute duration), for a buffed AC of 18 and Fire Resistance 10. Following that I'm casting Fly on everyone from scrolls (5 minute duration) and then casting Invisibility Sphere to conceal us all. (Spot check DC 20 + 1 per 10 feet of distance between us and them to see us, spot DC 40 + 1 per 10 feet of distance to pinpoint location and number.)
Alestair doesn't have to do anything in the initial power-up sequence, so he'll stand where the casters tell him to and get spells cast on him. His weapon capsule retainers are set up and loaded with one of each type of damage capsule in them.