Just tried updating 3.27 -> 4.11

Got the message about updating my license using winbox.

What about those of who don't use windows?
Can we update without using winbox?

While searching the forums I found a message that said I had to upgrade to 3.30 first. Is that correct?

Yes, updating to 3.30 ensures you have the right format license key to move on to 4.x

You cannot update the license without Winbox. The entire process is done via Winbox, and there is no CLI equivalent.

Sorry for saying this but I found it weird that they never built in a command line feature for this function. I wanted to do this job by script and I can't. I still have 100 routers to upgrade. Yawn.

You can make a script that upgrades all your routers to the last ROS version possible.
Some of them will halt @ 3.30 because the license is still old and need to be upgraded. but then you just need to log in and upgrade the license.
The script will run once again and it will upgrade your router to 4, then to 5
That's how i upgraded my whole network to NV2 (Pyton script runnin all the day long upgrading 1600 customers)