Linksys WRT3200ACM unable to sysupgrade

Hello community,
I have strange problem with sysupgrade from custom glibc build. After switching to initram it shows message sysupgrade like 245 /bin/mount not found...

My steps I tried:

Installing lede from stock using original LEDE build - working.
Then sysupgrade to mine LEDE - working. Next sysupgrade to original LEDE or mine LEDE not working
Revert back to stock firmware using uboot, install mine LEDE - working. Sysupgrade to other build of my LEDE - not working. Each time I'm trying sysupgrade from mine build of LEDE using glibc shows error message after switching to initram.

In initram does not work any command (ls, cd, cp, ps... ). every time it shows "command" not found.

My custom build is part of LEDE 17.01

Could anybody help me?