Not exactly.

Once you qualify for GO, your "cycle year" will reset and you will need to earn 120K in the next 12 months after you qualify for GO to hit DM.

Any time you change status, your "cycle year" reset to start on the date you changed status. So if you're SL now, you need to fly 60K miles before your SL year expires and you will be made GO, and then another 120K in the 12 months after you make GO to qualify for DM.

So once you make GO, you should continue to put miles into CX if you want to renew your GO or make DM.