Cannot Download Full Firmware UBI Classified Using the LuCI provided Page and Viability of Backup Questions

With regards to this post, a GL.INET GL-MT3000 device using OpenWRT version 23.05.03 was used.

When using the "Save mtdblock contents" firmware binary download interface within LuCI at http://192.168.1.1/cgi-bin/luci/admin/system/flash and selecting "ubi" as the "Choose mtdblock" option, downloads are incomplete. I am prompted to download a 246 MB file and instead of receiving such file, I receive a file that is about 70.8 MB. I tried downloading with two different browsers derived from Mozilla browsers and have a similar result (the binary files downloaded, however, have different checksums). It is my impression that OpenWrt is failing to provide the entire file or the correct file. My impression is that this might be a bug. Please advise.

According to https://openwrt.org/docs/guide-user/installation/generic.backup and https://openwrt.org/docs/techref/flash#nand-specific_tools_for_reading_and_writing_to_raw_nand , specific NAND-aware utilities or process should be used to backup or write to NAND mtd. Is the "Save mtdblock contents" tool of the "Flash operations" web page in the LuCI configuration interface NAND-aware?

I wish to properly backup my partition data. Please advise.