A-line skirts have the shaping along the side
seams - like this: /_\.
If you have the wider stockinette group along the edges, that would probably be easiest place to decrese, without having to worry about decreasing around the cable.
Mirl56 at Ravelry, too.
Learn from the mistakes of others. You canít live long enough to make them all yourself. Eleanor Roosevelt
Lady Feb Sweater
more shawlettes, socks