Listing all dates that a specific entry was made

Hi, I have been looking for awhile now, but cant find anything that i can make work.

In the attached file, I am trying to list all the dates that a specific entry was made. The data is A1:I20 and I hand-made my results in D27:U28.

In Column I the entries are 1,2, or 3(with 3 indicating both 1 and 2)

Sorry if this an inefficient layout. I am trying to collect data from 2 different sources, and make it useful to me.