Empty "Upgradabe to" field

RB433, RoS v3.30.
After pressing the Update Licence Key button, the Upgradable to disaperas. (See attached picture)

Allready rebooted, upgraded to 4.17, but still empty.

Can I upgrade further? Two boards made this today, and we have 6 more (433, 600, PC) which I need to upgrade.
licence.png

you can always upgrade to latest RouterOS, unless it is a RB112 device.

Thank you Normis!