until, when, seize, arrest
迨 centers on reaching a point in time or action: arriving at a moment (until, when) or catching up to someone (seize, arrest). The meanings share the idea of closing a gap to make contact.
迨 combines 辶 (movement) with 台, which likely contributes the sound. The character expresses reaching or catching up through motion.
The movement radical 辶 wraps around 台, like a path leading to a platform. Picture arriving at a station just in time to seize someone before they leave.
For タイ, imagine tying someone up when you arrest them: tie -> タイ, and the movement radical shows you catching up to do it.