This is another benefit to the Restructured idea.
The base simply drains “the Sun” and fires upon targets. No awkward questions about it’s mobility are raised.
It seems like the filmmakers knew SKB was a bad idea but they decided to do it anyway, moving as quickly through it as possible.
But it would have to be mobile to drain another sun. That’s what’s so ludicrous. Let’s apply SK to ep 4 and say it was about to destroy Alderaan at Tarkin’s behest. Would Motti (or whoever) have to go through a process to choose a worthy system to destroy in order to charge up and then destroy Alderaan? In other words the Empire/FO is committed to destroying two systems every time. “Let’s destroy Alderaan”. “Okay, well we need to find an appropriate sun to drain - any other systems in need of punishing since we’re stuck with a two-for-one deal?”