I understand that this is supposedly not possible on a Norstar ICS or 824 w/Dr5: doing a "Feature, *, 1, Hold" and blanking a line button. You supposedly cannot blank a line button.
Here's what happened, a 7324 set w/ 6 trunks assigned to it with the rest of the soft keys programmed with external autodial numbers. I assigned a 7th trunk and it appeared on the next button after the 6th line button (it over rode the external autodial). The customer requested it to be moved and after moving it, for whatever reason at the time, I was able to blank it. I even did "Feature, *, 0" to try and find it but it was gone. I had to go into programming and unassign it and then re-assign it to bring back.

Is there actually a way that a line button can be blanked or was I hallucinating?

I believe Feature *81 is used to move a line to another button, if that's what you mean. On later systems (not sure what year (version they started) you can set a line for appear only.
Not sure if any of this helps.
Steph

If you want to erase a feature off of a programmable key, you do a "F, *, 1, press a button then press"hold" and it erases the feature leaving the button blank.

I did this to a line button and it seemed to have blanked it out. Supposedly, this is not possible...or is it? Maybe I was imagining it.

Can you blank a line button?

No.

never heard of this, stay off the drugs