I was playing a recent QB using a pair of M5 lights in support of my infantry company. Opposing me was a mechanized infantry platoon with five or six halftracks in support. Normally this is no problem really, except that the M5s persisted in using canister rounds against the HTs, which had no discernible effect other than killing (quite reliably) their gunners. There were penetrations registered on almost every shot, but didn't knock out or noticeably hinder the operation of the HTs. The easy work-around was using a target command, which would apparently get the M5s to load the correct shell.
But I was wondering if it is possible to have the TacAI "upgrade" it's shot selection if, say, two rounds fail to kill the target? They had plenty of HE on hand, more than they had of canister rounds and did switch when ordered to target, so it wasn't a bug or anything. Just poor choice of shot on the part of the AI.