I went from RouterOS 7.x (I can't recall the exact version) to OpenWRT to 22.03.xx (again, I can't recall the exact version) about half a year ago.
OFFTOPIC: I mainly did it to get .11r seamless roaming to work (Mikrotik didn't update the wireless drivers for this device, supposedly for ROM size issue or whatnot) but that didn't work as expected (some older devices refuse to connect when .11r is enabled but that's another topic for another day....).
Now I wished to update to 23.05 (mainly to see if those .11r issues might be resolved) but I get a red warning that I must ditch my settings because swconfig won't migrate to DSA.
But after some searching with google I have to ask how am I even in this situation to begin with?
Most reports of this issue occurring is updating a device from 19.xx to 21.xx or so. But I started with 22.xx to begin with?
Is this a false alarm?
As far as the package manager searches go, I can't find any packages installed with either swconfig or DSA keywords. As far as looking at config files, I do have an swconfig in /etc.
So how did this happen? Was the transition from swconfig to DSA device-dependent and this particular device "neglected"?
Is there a workaround?
I use these devices as "dumb WiFi AP" (no routing, no segregated guest network, just pure WiFi AP access to the local network [the effective "router" is an x86_64 home server running Gentoo and I have 2 WiFi AP to cover a 3 story building]).
I really don't want to start from scratch again after "just" half a year (or so). The release notes of 23.05 say that it should be possible to easily update from 22.xx.
Hi
well, sort of ...
main change is in network config
rest is more or less similar
if you are good with understanding human readable config files then, best way is to make a config backup and save on PC
- then reset your 23.05 router to defaults, it will ensure that network setting start from default DSA
- configure your basic network/wifi settings, to be sure that you understand DSA
- install any missing packages you want
- open backup archive on your PC and use it as a textual guide, you will need to understand what settings are in old config , for ex /etc/config/snmp and try to implement them again from LuCI web
it is not ideal, but more than nothing 
Thank you for the replies.
I went ahead with a forced upgrade while unticking the "preserve config". Adn then did a "hard reset" through Telnet just in case.
But my "worst fear" just came to haunt me because these devices receive power through thier PoE "uplink" ports, so with WiFi disabled by default, I can't access them through their firewall (they are trying to do NAT/routing/firewalling from their uplink ports like most regular routers do by dafult with pretty much any OS).
So I will have to find long cables and 24V adapters and power them through their power jack ports until I configure them (at least up to the point where they let me in on their "uplink" ports).
By the way, setting up a "bumb AP" with this new DSA interface was easier than how I remembered from the old swconfig. I simply added the WAN port to the bridge, set the protocol to DHCP and DONE. If I recall correctly, there were a few more steps involved in later OpenWRT releases (on all routers).
Now it's time for me to get to the tedious work of setting up DAWN and then read a ton of text about how to potentially get .11r to work (even with "legacy" devices around -> or alternately try to install LineageOS on those old tablests/phones if that might helps, though I guess it's more about WiFi chipset+driver than the OS itself and LineageOS mostly tends to keep the original manufacturer drivers).
Any tips on that? (.11r setup)? There are a bunch of parameters to set.
Or is DAWN "good enough" on it's own?
I tend to do WiFi based calls (WhatsApp and whatnot) while moving around the estate.
Edit: Ahh! OK! Looks like with this version of wpad-mbedtls, .11r is pretty much ticking the checkbox to enable it and it's theoretically all done (the mobility domain is auto-calculated). Nice.
Now on to testing old tablest/phones...
You should've build them w/o firewall/nftables since they are dumb APs.
I used to build my own binary packages for my actual routers (optimized for speed with -O2 instead space with -Os through GCC) back in the old days when I used SOHO boxes as actual routers (before I transferred that task to my "home server" which is basically a glorified custom-built NAS based on x86 PC parts, including ebay-salvagaed 10Gbe Mellanox cards between the NAS and my worstation) but I don't currently have a toolchain set up for building OpenWRT from sources.
Moreover, I have pretty much zero experience with debugging/unbricking Mikrotik devices (I never tried to customized them before I got fed up with their dubious wifiwave2 policy). And there is ample enough space for the standard pre-built package plus these two little addon packages I needed (full wpad and DAWN + their dependencies).
So, in the end, it was much easier to grab a ladder and a power cable. (Having 10 rather than just 2 devices would be a different story.)
It's still a good advice though if the devices are much more out of physical reach (like attached to a tower) rather than lazily hidden inside a residential building (not that hard to reach).
I have 150+ of WAP AC/AC2 w/ PoE in (one) warehouse...
I rather invest 30mins in firmware build than whole week on a ladder. 
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