3300 c.i. is certainly large enough capacity to do what you want for some people --- I know that it is for me. I'm sure that it's not enough for others. I have no idea if it's enough for you, as I don't know what how bulky and heavy your various gear items are, nor what kinds of items you feel worth carrying that I don't (or vice versa). The variation in bulk and weight of gear carried is very large between individuals.

Since you're a long-time hiker/backpacker I presume that you have most or all of your gear already. Since you also already own the pack then ... ??? Make a list of *every* gear item you plan to carry. Do a test pack, literally load the pack just as you would for the trip. Estimate whether available space allows for the food you think you might need. If you're not certain, estimate something on the order of 700 c.i. --- this also depends on the amount and type of food you carry, of course.