Hello everyone, I don't know how useful this is going to be, but a couple of month ago I went from running CFW to going clean by downgrading by restoring a clean backup before updating to the latest firmware. I haven't been banned, so far, though I did little more than using a few homebrew apps and installing NSP files while offline.
Banned? N
Can you use the eShop on the Switch? Y
If you cannot access the eShop, when was the last time/date you were able to?
Did you restore a clean hack-free NAND before going online? Y
Do you get the error code 2181-4008 trying to update your games? N
Do you get error code 2137-7403 trying to update your system firmware? N
Can you login to Nintendo's website using your linked Nintendo Account? Y
SX OS used? N
Did you make an SX OS EmuNAND with a clean hack-free NAND then stay offline with it? N
Trimmed .XCI? N
Did you connect to the Internet with SX OS and/or to activate the license? N
Did you play any .XCI files online with a certificate/header? N
Do you have a certificate/header ban (look for error code 2124-4025)? N
Lowest SX Version used when Online/Offline (NOT Switch System Firmware)? N
What do you use Non-SX OS LayeredFS for? N
Did you connect to the Internet with a non-SX OS LayeredFS Inject? N
Played online w/ Non-SX OS Layered FS Injects? N
Did you inject an .XCI certificate using LayeredFS to play online? N
Used DevMenu? N
Installed any .NSP? Y
Did you connect to the Internet w/ any .NSP installed? Y - Only the time required to set custom DNS to stop communications with Nintendo servers
Did you play any .NSP installed online? N
Did you perform any CDN/Freeshop downloading with your own Switch's certificate? N
Did you update your .XCI/.NSP games online? N
Did you ever use ReiNX? Y
Homebrew/non-SX CFW Used? Y - Checkpoint, Edizon, Tinfoil, Goldleaf, NX-Shell, Retroarch
Connect to Internet with homebrew/non-SX OS CFW? Y - Retroarch
Connect to eShop while using CFW/homebrew? N
AutoRCM? N
Did you update your firmware using ChoiDujour or ChoiDujourNX? N
Did you install the exFAT update offline? N
receive-lp1.dg.srv.nintendo.net blocked and/or "Don't Share Usage Information" ticked under "Other Settings"? N
Do you have eclct disabled (look for pm.kip under sysmodules/modules)? Y
Do you have creport enabled (look for a folder named 0100000000000036 under titles)? Y - However I'm not sure about the answer while I used ReiNX
What firmware(s) were you on when you cleared error logs prior to going online? N
Wi-Fi settings deleted in CFW? N
Console/Account Region(s) EU
What device(s) do you use to send payloads with? Computer, NS-Atmosphere dongle
Do you enter RCM by bridging pins 9 & 10 together? Y - Also used pins 1 & 10
Additional Comments: As far as I remember on one occasione I've played in local wireless with a non-modded Switch, both running the game from cartridges. Until January I used ReiNX, then Atmosphere.