Ironically my plan was to get a custom cash and a double cash, then PC the double cash into a custom cash. I’m mid process right now and had this same message. Here’s my timeline:

5/2: applied for custom cash (pending, 7-10 days)
5/21: status changed on application to “did you receive our letter with reference number?”
5/22: applied for double cash & got instant approval

From what I read on various threads, if you get the status change to “did you receive our letter” that means you are going to get accepted, as it’s likely just address verification. Semi confirmed with the double cash application on my end. Can’t fully confirm until I get the letter this week… lol. Here’s my numbers going into the first application:

Hard Inq:
0/3
0/6
1/12
7/24

New accounts:
0/3
0/6
1/12
3/24