It is for sure there wont be any CAU8 GBs anymore. I would love to get a chart showing how much cargo space the specific CAUs take up, so I know, if I have to do anything in advance to .86 to not get a cheat message.
CAU 8s will fit in the gunboats, but it will require you use the weaponry that takes less cargo. ie; You choose defense or offense. The larger, slower gunboats with higher cargoes will have the ability to mount larger armors while keeping strong firepower. But they are far weaker to fighters and bombers than their smaller, less armored, more agile brethren.
For example, the Kusari and Bretonian Gunboats.
Kusari gunboat is very small, very fast, but has only 350 cargospace.
Bretonian gunboat is huge, slow, but has 480 cargospace. It will be able to fit a CAU 8 AND a lot of firepower, making it perfect for killing other gunboats, but weak against fighter swarms.
(These are .85 cargo values and may be subject to change.)