Sourdough starter "storage" for 31/2 weeks...

We are heading out on a 3 1/2 week trip and I was wondering what to do with my starter. I keep it in the fridge and may bread every week and a half. By that time it tends to crust up. I can only imagine the crust after almost a month... I store it in the King Arthur plastic Sourdough bowls, covered but not sealed...
What should I do?
Thank you...