Procedure for transitioning from Leased TV Video STB to Customer owned TV Video equipment Activation

I have purchased several XG1v4-A TV STB's and I want to transition from Leased TV Video to Customer owned TV Set Top Boxes.

I successfully registered these boxes with Comcast for activation in my account, waited the 30 minute delay period before I attempted to activate.

However, after numerous attempts (4-5 hours with another successful registration of the "SN") to Activate this TV video equipment, I only got as far as the "Entering Entertainment Experience" screen, that then goes back to an "Requires Activation screen".

Without a specific written procedures or online guidance this has been much more difficult that is should be....

My questions are:

1) These STB have 2 serial numbers on the Label, one identified as "SN" and the other  CC SN (CableCard SN in the diagnostic screen) also numinous MAC's :

So, which "SN" should be used to register this equipment (I used the "SN") as when I asked the Live Agent they didn't answer. (figured it didn't matter)

2) I was later told that, I could not have the current Leased STB's activated and then activate the customer owned TV Video equipment?

If that is true, how would I deactivate the Leased TV Video STB after, successfully registering the Customer owned equipment, and before I activate the customer owned TV Video equipment?

Also, If the Customer Owned TV Video equipment will not activate, will it be able to reactivate the Leased equipment previously activated and still in my possession?

Feedback:

Purchasing my own equipment is by necessity.

I have 2 each XG1v4-A in my system and in the last 4 months,

I have replaced 5-6 XG1v4-A STB's mostly for fan noise, one would not work after activation and one that had a bad X1 DVR Play-Back (skips & stops during playback also serious video Pixelation) that made it impossible to enjoy record programs