Congrats....I am waiting for the day my 5/24 hits... 
@MJ-san wrote:Adding a data point. Was at 5/24 as of 3/20. EQ and TU show exact dates of accounts being opened, EX shows month opened.
I had cards showing opened 10/6/18, 6/19/18, 3/1/18, 8/26/17, 3/20/17, 3/1/17. I also had a refi mortgage and new car lease show up in 6/18 (those don't count).
On 3/21/19 I app'd for a Chase United Club card (FICO 744, overall UTIL 13%) and got the "we'll get back to you" screen. When I called recon, was put through verification (TXT to cell, read back CID from existing card), app was processed and approved immediately and shows up on my Chase online banking screen. I didn't have to explain anything - I expected having to explain that as of today I was at 4/24 or needing to wait until after the 4/1, but didn't need to.
There are datapoints all over the place about this. If I had to guess then it all comes down to which report chase decides to pull and how that particular agency reports opening dates. Personally I am probably just going to wait until the following month before apping to avoid any hassle.
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