During the Anniversary Sale I CCU'd (Cross Chassis Upgrade) my Constellation Aquila -> Carrack and my Reliant ($50 starter ship with LTI) to a Khartu-Al fighter.
The nice thing about CCU'ing is that it keeps Lifetime Insurance or package of what you had and upgrades the ship. During sales and new ship offerings you can select something you already have for an upgrade vs "melting" the package for credit and purchasing the new ship (as an option).
https://robertsspaceindustries.com/pledge/ship-upgradesIn the past - folks with game packages were a bit limited on what they could upgrade, and it likely generated a bunch of customer service tickets to fix things. Now you can just bump things up on your own.