I have a recipe for pickled eggs that requires pressure canning @ 250 degrees for 30 minutes, with a shelf life of 9 months. I know in the past that pickled eggs don't last that long as they are eaten long before that. The recipe calls for 5% vinegar and 2 Tbsp salt per quart. Would this be a fair time for shelf life, or could the shelf life be extended beyond 9 months?
According to the National Center for Home Food Preservation, there is no home canning recipe for pickled eggs. All the recipes that are tested and research-based (they only one recommended) are for refrigerated eggs only. I am not sure where you found your recipe, but I do not recommend you use it. And as far as the shelf life, no it can not be extended. Here is the time for best quality...
After making the eggs, the eggs require some time to season (i.e., pick up the flavors from the pickling brine). Keep them refrigerated at all times. If small eggs are used, 1 to 2 weeks are usually allowed for seasoning to occur. Medium or large eggs may require 2 to 4 weeks to become well seasoned. Use the eggs within 3 to 4 months for best quality.
Here is the link to the site for further instructions: http://nchfp.uga.edu/how/can_06/pickled_eggs.html
I hope this helps and if you need anything else, just let me know.