I have a Linksys E8450 and I installed openwrt about a year ago. Somehow initially I installed snapshot r18646-3869ccbcc8. I've always been on this snapshot and would like to move to a stable release.
I did something stupid and upgraded to the non UBI version of my firmware. I did do a force upgrade because I thought it was the proper one, but it was not. I've since been able to find the correct firmware for my device but regardless of what I do there seems to be no change. Any advice would be appreciated.
Since it sounds like you've done all the right things, I suspect you just have to wait for the DRAM-based pstore files to go away. Unplug the device for a couple minutes and see if that fixes it.