Depth Bonus in Mixed Large Units

As already known, there is a large unit depth bonus for FP armed with long spear against enemy mounted or foot. Would that bonus still apply to a large unit that has a front unit armed with long spears, but a rear unit armed with another weapon?

For example, in the Late Imperial Romans (West) 285-409 AD list, one can form a large unit with Comitatenses (FP, long spear) in the front, and a Supporting Sagittarii (T) unit in the rear.

No it just soaks up losses so front rank can stay at full strength for longer.