Notice Explaining USCIS Actions Was Mailed

[Arcane]

Hi,

Today I received this message from USCIS for my wife's COS,

Notice Explaining USCIS Actions Was Mailed

On June 14, 2021, we began reviewing your Form I-539, Application To Extend/Change Nonimmigrant Status, Receipt Number '*****'. We mailed you a notice informing you of the action we intend to take on your case. Please follow the instructions in the notice and submit any requested materials. If you do not receive your notice by June 30, 2021, contact the USCIS Contact Center at www.uscis.gov/contactcenter. If you move, go to www.uscis.gov/addresschange to give us your new mailing address.

Can anyone pls explain what this means? Most of the information I received for an H1-B visa. Cannot able to find anything related to H4.
1) Mostly I saw comments mentioning RFE or NOID?
2) If it is decline won't they say directly?

Thanks in advance.
Sri

[Arcane]

 

Edited June 16, 2021 by Arcane