It looks like the 13 Jan 2009 compressor stall (see
BBC NEWS | World | Americas | NY crash jet had earlier problem) of the same unfortunate A320 which coincidentally was to land two days later in the Hudson might be another example of a HP compressor stall to be corrected by a CFM software mod.
In practice, if a susceptible engine has a demonstrated compressor stall, would the CFM software mod typically be made before that particular engine flies again?