2 official rulings from Bandai, last ruled Mar 28, 2024. Straight answers to how this card actually resolves.

I have a Digimon in play with this card in its digivolution cards. [BT1-087]/[T.K. Takaishi]’s effect adds a yellow card from my security stack to my hand, and adds a card to my security stack with . The number of cards in my security stack ultimately remained the same, but can I still gain 1 memory from this card’s inherited effect?
Yes. added a card to your security, so you gain 1 memory.
Ruled Mar 28, 2024
This Digimon gets +4000 DP from its effect. During the same turn, I end up with 2 or fewer cards in my security stack. Does the +4000 DP granted by this card’s effect go away?
No. So long as you had 3 or more security cards at the time you activated this card’s inherited effect, the effect will persist until the end of your opponent’s next turn, even if you end up with 2 or fewer security cards.
Ruled Mar 28, 2024
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