Extract Parameter question

From a Trailfile contect point of view, is there any difference in what data is written to the trail by getbeforecols vs getupdatebefores?

I do understand that getupdatebefores applies to all TABLE statements following that parameter placement while getbeforecols is at TABLE level and is applicable only to Oracle DB.

Also, can getbeforecols be used along with NOCOMPRESSUPDATES?

Trying to figure out a way to avoid having column-level mapping in a classic replicat where we evaluate any missing values and set those columns to values in the Before image using "before.columnname". Trying to emulate LOGALLSUPCOLS and avoid having to update the replicat param file everytime a new column is added to a replicated table.