Airtight Alibi

• WOTC Official Reminder Textofficial rules
  Flash — You may cast this spell any time you could cast an instant.

• WWizards of the Coast2024-02-02
  Official Ruling
  If a suspected creature loses all abilities, it will lose menace and "This creature can't block", but it won't stop being suspected.
• WWizards of the Coast2024-02-02
  Official Ruling
  When an effect suspects a creature, it becomes suspected. It gains menace and "This creature can't block" for as long as it's suspected. It stays suspected until it leaves the battlefield or another effect causes it to no longer be suspected.
• WWizards of the Coast2024-02-02
  Official Ruling
  If a creature is already suspected, suspecting it again won't have any effect.
• WWizards of the Coast2024-02-02
  Official Ruling
  Being suspected isn't a copiable value. If a permanent becomes a copy of a suspected creature, it won't be suspected.
• WWizards of the Coast2024-02-02
  Official Ruling
  There's no limit to the number of creatures that can be suspected simultaneously. Suspecting a new creature doesn't cause other creatures to stop being suspected.

Rulings via Scryfall