Package Assembly Timeline for NAmILG (WeGreened)

I am currently working with chen immigration for my EB1-B petition and they are currently assembling my package to be sent out to the USCIS. However, it took almost 7 weeks for my NIW petition to be sent out after sending them all the documents ( My documents were sent to them on 1st July and they sent the petition out on 18th August). I am now worried about my EB1-B timeline. I asked them how much time they will take and I got this fixed response.

"We apologize but we are unable to provide a set timeline for package review and assembly, as the time it takes to prepare your package will depend on the quality of evidence received and our current caseloads."

No doubt they are really good at preparing your case but these additional 6-7 weeks of wait time worries me a lot.

How much time they are currently taking to send the petition to the USCIS? Are there any improvements in their speed for assembling packages?

Any response will be really helpful.

why not submitting your EB-1B petition by yourself since you have all the documents?

I prepared and filed my EB-1A case by myself. You can submit your EB-1B without the attorney. Waiting is not a good thing since you can not control.