This episode is such a "227" classic.
This marks Jackee's (Sandra) last appearance on the show. I will say this- she went out with a bang!
There's no explanation of her character leaving, but this episode rocks. It's so funny and kind of a bitter sweet end for Sandra. Throughout the whole series Sandra and Mary have been fighting and arguing and in Sandra's last episode Mary steps up to help her when she knows that Sandra has been treated unfairly. Can we say the two ended on a friendly note?
If so, that would be very ironic because the reason of Jackee's departing of show was because of a feud between her and Marla Gibbs. After Jackee won her Emmy, Marla (who was the head of the show) didn't send flowers or allow the other cast members of the show to throw her party.