How did your ds do over Christmas break? Any other breaks so far in the school year? Does he take awhile to get back to baseline after a week off? Basically, I'm asking to see if you have any ability to show the school documented regression in his past - it is a shorter time span so it can be tough, but even if he takes a week to recover from a week-long break, associate that to how long it will take him to recover from a 3-month break.
You do need to reconvene the IEP meeting, which you are allowed to ask to do at any time. It will involve all his team members and the discussion about what to do for summer. I would suggest bringing a family member or friend with you, as well as notes. These meetings, even when they go well, can be stressful and details can be forgotten in the midst of it. I know when I walk into a room full of people (dd has an ASD dx so we work with a large team!) around the table, all from the school, it can feel intimidating even if I'm not expecting any problems.
You do need to reconvene the IEP meeting, which you are allowed to ask to do at any time. It will involve all his team members and the discussion about what to do for summer. I would suggest bringing a family member or friend with you, as well as notes. These meetings, even when they go well, can be stressful and details can be forgotten in the midst of it. I know when I walk into a room full of people (dd has an ASD dx so we work with a large team!) around the table, all from the school, it can feel intimidating even if I'm not expecting any problems.