Generally, with that rig, you use the aft sail for upwind work if you are going to be tacking at all frequently. As you say, the forward one needs to be rolled up to tack. But you can effectively use the forward one upwind if you are going to be on one tack for quite a while.
The forward one is more typically used for reaching/running in lightish air.
This was a somewhat common rig before the development and refinement of the code zero/rope luff furling
systems. It gave you a small and a big jib
immediately available for use, but at the cost of extra windage and weight aloft. Its still a useful cruising rig, but today, the more 'modern' solution would be to put the forward sail on a rope
, which you can leave up for reaching running work, but take down for upwind work to reduce windage and weight and wear and tear on it.