Hi, I'm coming from a Netgear WNDR3700 (17.01 LEDE) to a Netgear R7800 (18.06 OpenWRT) -- is a configuration migration (restore) from the backed up 17.01 to 18.06 possible, and if so, do I need to tweak anything else to make that work? Would save me a lot of time ... thank you!
No, especially network (switch) and wireless configuration differ between different devices (models).
You could backup configuration files and use them as a reference when configuring the new device
... but note that network/wifi hardware related settings will have changed between WNDR3700 and R7800 devices, plus e.g. switch config logic has changed somewhat.
Thanks all for the fast replies -- I guess having the backed up configuration as a reference and re-implementing it on the new device should indeed do the job.