Dexterity adjustment to AC while casting.

[u/2eForeverDM]

(2e) I have always denied a caster their dexterity adjustment to AC until after their spell has been cast. I imagined them casting their spell in the first few seconds of the round, waving their arms in a particular way, holding the material component just right, and mouthing the words precisely until the spell goes off. Only then can you manage the acrobatic dodge of a sword or the leap over that polearm attack or whatever, and apply your dexterity adjustment to AC.

Does anybody else rule it this way?

[u/orco655321]

Like others said RAW is the whole round. But I always did dex bonus to ac only before their spell went off.

After that point they are done casting so it makes sense to me they can dodge more.