I'm not sure about the February 27 patch.
I did some test today in the same household from yesterday (8 sims) and i created a room with 8 pianos. One of my sims (piano skill 5) didn't have the option to practice piano in the menu. After clicking on another piano, the option appears. Then the 8 sims could practice (including the one with skill level 3).
So it seems that the option to practice disappear at random.
@crinrict today it did, yesterday the sim with level 3 couldn't practice in 2 different pianos (the cheap and the expensive one from base game)
Tested this with the City Living keyboard and all family members had the practice option, including one with level 6 piano and a 3 star celebrity.
