If I understand, you plan on buying a new tank, and you want to run your old established filter on the new tank. Yes, if you do this, your new tank will have no cycle if the fish load is not dramatically increased too fast. I Presume you are going to transfer the fish from the old tank to the new tank? Otherwise, you will be robbing the old tank of its filter and making that old tank go through a cycle in order to spare the new tank a cycle. Unless, you have two filters on the old tank?
How long do you have to run the established and new filter simultaneously? I would have thought 2 to 4 weeks for optimal colonization, but GM's confident answer of 10 days makes me wonder if I am too conservative.