Reapply CPP disability, no final decision at SST

Good Morning,

One of your videos states you CAN reapply for CPP Disability if you didn’t get a decision at the SST. My question is, When do you apply from the beginning with a NEW application. My doctor is supportive and suggest we start from the beginning. My deadline was last week. Do I apply soon? Or do I have to wait a few months to reapply with NEW application?
Thank You