BDT refers to an old Q post referencing the NY failed terror attack before it happened.
Dec 11 2017 12:23:09
Q
!ITPb.qbhqo
Do you believe in coincidences?
"Blunt & Direct Time"
BDT.
Think currency.
Think fireworks.
Thwarted.
Message delivered.
These people are sick!
Q
BDT is the ticker for the Bangladeshi currency, where the attacker was from. Additionally, the terror attack was thwarted, so there were fireworks instead of explosives in his pants.
Q post 327, if you use one of the Q search sites.