Alcatel Unleashed

I have stack of three 6850 with such firmware:
6.4.4.441.R01
Uboot Version : 6.4.4.213.R01
Miniboot Version : 6.4.4.213.R01

After reading upgrading matrix wont update firmware from current to latest 6.4.4.645 R01 directly. Can i do this? Or I need update to intermediate versions step by step. And did I can upgrade without upgade U-Boot/Miniboot? Thanks!

you can update directly to 6.4.4.645.

there is an upgrade guide only in the master release stating from which previous master Versions (as 6.4.3.X or 6.3.1.X) you can upgrade.

Within a single master Release (6.4.4.X) you can up or downgrade without problems.. you only need to be careful, if you upgrade to another Masterrelease e.g. 6.4.5 or 6.4.6 which may require a fpga/uboot/miniboot update as well.

also when downgrading from such a version you may need to downgrade fpga and uboot according to the release notes.