Use TEXTJOIN in an array formula:
=SUBSTITUTE(TEXTJOIN(", ",TRUE,IF(ISNUMBER(SEARCH("*/*/*",TRIM(MID(SUBSTITUTE(A1," ",REPT(" ",99)),(ROW($1:$25)-1)*99+1,99)))),TRIM(MID(SUBSTITUTE(A1," ",REPT(" ",99)),(ROW($1:$25)-1)*99+1,99)),"")),".","")
Being an array formula it needs to be confirmed with Ctrl-Shift-Enter instead of Enter when exiting edit mode.
TEXTJOIN was introduced with Office 365 Excel
![enter image description here]()
If you do not have Office 365 then the output will need to be in different cells for each "date"
Put this in B1, copy over and down:
=IFERROR(SUBSTITUTE(TRIM(MID(SUBSTITUTE($A1," ",REPT(" ",99)),(AGGREGATE(15,6,ROW($1:$25)/(ISNUMBER(SEARCH("*/*/*",TRIM(MID(SUBSTITUTE($A1," ",REPT(" ",99)),(ROW($1:$25)-1)*99+1,99))))),COLUMN(A:A))-1)*99+1,99)),".",""),"")
![enter image description here]()