"nand erase" : did I nuke caldata_backup on netgear_wndr3700-v4?

I have a netgear_wndr3700-v4. In the process of un-bricking it, I did :

nand erase 0x6c0000 7485746

... but the "size" was interpreted as hex (~122 meg), so it did :

NAND erase: device 0 offset 0x6c0000, size 0x7485746 ath_nand_erase: 0x6c0000 933

I think this erased caldata_backup , which is at 0x1fc0000-0x2000000

Do I need to restore caldata_backup (from caldata) ?

Also, when I flashed the netgear factory firmware, I got tons of error messages, such as :

Empty flash at 0x0553fc3c ends at 0x0553fc40

jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x05540000: 0x7f7a instead

Everything seems to be fine w/ OpenWRT, but I wonder if I broke something.

Do you I need to fix anything ?

Thanks !