Artisan sourdough bread We buy artisan white sourdough bread from a baker.  when we first got it the loaves were lovely for sandwiches.  Lately for a couple months now the loaves having been coming with large holes maybe in the middle on the top side or even lacey big holes making it hard to use and sell to customers.  I have talked to the bakery about the issues we are having and tryed asking why this is happening.  One double large loaf I could only use 6 slices to make sandwiches from.  Help I really want to support local and we love the flavor of the bread.  They say its just how artisan bread is  but why was is so good for 6 months and now for 2 months so different.  The holes are about 2 to 3 inches  I don't even mind 1 inch every now and then on the bread  Its the 3 inch and lots of 2 inches like lace that I just find hard to serve  my customers.  Any explaination for this big change and difference in the bread.  If I bought whole wheat sourdough would I have these problems.
Thanks so much for taking the time
As moscafj mentioned in comments, the baker likely changed something in the process or recipe.  If the general question is why big holes happen in lean artisan breads sometimes, there are several possibilities, some of which I enumerated in answer to a previous question.

In very general terms, the more bread is "handled" during the process of a rise, the more even the crumb will be.  (That is: "even crumb" = very fine small even holes.)  This can involve additional kneading or folding or "punching down" periodically during the rise.  The most relevant, of course, is handling and shaping before the final rise where the final air bubbles develop.

The baker is correct that many "artisan bakers" value a texture that has large (often irregular) holes.  And many consumers like that.  It may not be great for sandwiches, but that is not the only use for artisan bread.  If, however, the holes are not evenly distributed but are gathered in certain places (like the middle of the top of the loaf, as you mention in the question), that could indicate inferior kneading or shaping technique, as well as perhaps an overproofed final dough before baking.