First From A4.2 if you split a moving stack, one part of that former stack must finish moving before continuing with the rest. So if you split the stack to have some units search they must spend the 1MF to search separate from the rest of the stack and are no longer considered moving as part of that stack even though they may remain the the same location. This means that if the units searching want the protection of the AFV from Armored Assault, the AFV MUST be part of searching stack and is no longer part of the leader stack. Also see the Q&A below.
A4.8, A12.152, & D9.31
An AFV and an MMC declare Armored Assault (without declaring Assault Movement) and as a stack move into a new hex where
the un-Pinned MMC now wants to make a Search attempt. According to A12.152 “Regardless of the outcome, that unit or moving
stack is TI for the remainder of that Player Turn.” But according to A4.8: “TI status is incurred by Infantry engaged in various
tasks...” (i.e., the AFV is not subject to TI status). So is the Search allowed despite the AFV not being subject to TI?
A. Yes, but the AFV must end its MPh with the searchers
If the AFV wants to continue with the leader, then while the searching units are searching, they are no longer moving with the AFV and no longer get any protection from it.
I would think the searching units would receive 0 TEM (nam and tank +1) while searching since still part of the armored assault at that moment.
In this case the tank is no longer moving with the leader, it is moving with the searching units.
