[Android] How long does WhatsApp keep stickers after those are deleted from 3rd party app?

[BattleShipPark]

Specifications
OS Version: [FILL IN]
Device Manufacturer: [FILL IN]

Stickers

• My stickers do comply with the sticker requirements (512x512 and < 100 KB)
• My tray icon does comply with the requirements (96x96 and < 50 KB)
• I am using WebP images for stickers.
• I am using PNG images for stickers.

Problem Description
[FILL IN WITH DETAILED DESCRIPTION OF THE PROBLEM]

Reproduction Steps
[FILL IN WITH DETAILED REPRODUCTION STEPS]

Head of Commit
[Do you have the latest commit from master? If not, please update your repo to the latest commit in master, and try again. If issue still occurs, please note down the commit hash (from this repo) here:]
[Commit hash]

Links
[FILL IN PLAY STORE LINK AND/OR LINK TO SOURCE CODE ON GIT]

To export stickers I need to download them to the device, which means the more I download the more I use storage in my device.
So I am planning to add storage management that users can delete downloaded stickers.
My concern is that 'WhatsApp can use stickers event after I deleted them in my app?'

I made an experiment that I exported stickers to WhatsApp and I uninstalled my app.
I can use stickers in WhatsApp without my app and I understood WhatsApp stored stickers separately without my app.

BUT, How long does WhatsApp keep stickers after those are deleted from 3rd party app?
If WhatsApp keeps them only for several days as cache, I must not let users delete stickers.

Thanks.