Best way to update a 6.1.0 ReiNX Switch?

[MDragon]

I have an old modded Switch I haven't touched since December 2018 (or perhaps April 2019) and that I'm finally getting my lazy/forgetful behind to use. Thus far, I've been able to do the following again:

1. Added my old modded Switch's SD card backup to my current SD card (256gb so no worries about space)
2. Followed the guide below to install the latest TegraRcmGUI and ran both the latest TegraExplorer.bin as well as an old "hekata_ctcaer_5.0.0.bin" payload I had on my computer
   1. Guide used (as can't embed urls sadly): nh-server.github.io/switch-guide/user_guide/emummc/sending_payload/
3. Booted Switch into RCM mode (which happens by default yay) and ran the old hekata payload mentioned above. (Don't think it matters which payload to run since they both end up on the simple boot screen?)
4. In the simple boot screen, I used the Power and Volume- buttons to go to SD card -> bootloader -> payloads -> ReiNX.bin (dated 11/28/2018). Ran the payload
5. Once I got the Switch to finally boot in like 3ish years, I went and checked the system version which said 6.1.0 ReiNX

As far as I've heard, I need to update Atmosphere (which I think I'm using but guess not the actual CFW?) and update the Switch firmware as well (using Daybreak?). However, this is where I'm not finding any clear (or clearly up-to-date) info. For example:

1. What do I need to update first? Hekate (??)? Atmosphere? Move away from ReiNX to a different CFW?
   1. I keep seeing special instructions regarding if below Atmosphere version 1.0 and - assuming I remember correctly that ReiNX is an old CFW built on top of "atmosphere" - I can't tell what atmosphere version I'm using. Even checked ReiNX Github releases page but no mention there
2. Once I do the above CFW and payload updates, is it safe for me to try to immediately update the Switch firmware itself? Or are there other steps I need to follow on this old man Switch before I proceed?

Thank you for any and all help!

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Edits with new findings:

1. I am most certainly NOT using atmosphere 1.0, given that came out in September 2021:
   1. https://github.com/Atmosphere-NX/Atmosphere/releases?page=2
2. Given above, I'll try following the update atmosphere -> update hekate -> update firmware steps listed below:
   1. https://nh-server.github.io/switch-guide/extras/updating/

Final edit in case it helps anyone:

As home page of the nh-server.github.io guide states: "Custom Firmware is not permanent with current methods, and will be unloaded upon rebooting the system."

Which made me realize that I can just redo the SD card entirely. Thus I simply followed the basic User Guide for all relevant steps, which involved partitioning the SD card and taking it from there.

As a disclaimer, I did have AutoRCM as well as original NAND backups. Your mileage may vary.