Quote Originally Posted by Ace of Spades
Thanks for the help, everyone. I'll have to try that tonight (or maybe I shouldn't if I'm gonna' get creamed..)
I don't think that's likely to happen. After moving the last ship in the chain into position, you will still have to press end-year before the army move is a valid one. This means that, on the next turn, you will get to see the size of the rebel stack and examine the troop types/quality to assess what sort of invasion force to take.

The only hiccup would be if it turns out you under-estimated how many of your troops this is going to require to be sure of success and, if understocked with troops (remember what I said about the garrison in the province they embark from needs to still be strong enough after they've set off?) then you may have to delay a few years to both mobilise enough of them at your training centres and, perhaps, maneuvre them into the departure point.

You CAN move multiple units from multiple provinces to the target province but this presupposes that you've constructed numerous ports and all the relevant ship routes are valid. If this is very early into the game, that might not be the case e.g. you've only had time/money enough to build just the one.