Updating one toolbox of SNAP via comand line

Dear @marpet or @lveci,

If I want to check and update only the S1TBX (which means with all its modules) via command line, how could I do?

I have found how to get it from one specific module, but not how to do it toolbox-wise.
Is it a clever way to do that? As S1TBX has several modules (which can increase on time) it is a bit more complex that I expected.

Maybe there is an option that I do not know.
Can you please tell me how to?

It is possible to update only the kit module of s1tbx.
This kit module has dependencies to all other s1tbx modules and those will be updated too.

snap --nosplash --nogui --modules --update org.esa.s1tbx.s1tbx.kit

Maybe you also want to update the RadarSat Toolbox too. Then call also this:
snap --nosplash --nogui --modules --update org.csa.rstb.rstb.kit


Thanks @marpet!

This helps me exactly in what I was needing.