You should let go of all pumping sessions now as you have no intention of ever pumping again and you are with your child and your baby can nurse at all those time you would need to pump. And you can begin to drop actual feeding as you see fit and work for your child.
I however want to gently encourage NOT to get fixated on a date. For a number of reasons. The first is you should be your childs main and only source of nutrition until a year. If you begin to wean BEFORE that point you won't be. 2nd. Having hard date to wean by puts so much pressure on the mother and is sooo confusing for a child. You would not suddenly remove a child favorite lovey with no reason or explanation and I assure you your child is 1000x time more attached to nursing than any blanket or toy. A year is where weaning is to begin. Not end abruptly. It's where you begin to trust your child to eat solids and fill the gaps where there are none with your breastmilk. For most dyads getting to the point where a toddler can be trusted to ingest enough food to nutritionally make up for breastmilk is a process that does not commence on a certain date. It's a process. A process that when done slowly and gently can be stress free for both of you. The 3rd is that your child will at around the time of his first b-day go through the worst most painful bout of teething pain that he has yet experienced. I personally think not being able to nurse through that will be horrific for both you. But much more so for your baby.
I fully support you putting down the pump FOREVER right now if you are already home for the summer. But I think saying "I need to be done with this in 11 weeks PERIOD" is a recipe that I have seen to have miserable results time and time again here. If your goal is to wean as close to the year point at possible, I think you should nurse on demand all summer while really stepping up the solids game. I take nutritionally very seriously and just to give you an example my son was eating 3 full meals a day and 2 snack by his first b-day and I STILL did not trust that food was able to replace my breastmilk and it's antibodies and all he was getting from me completely. So watch your son. For food an intake and places that you DO feel like you can substitute in solids and plan to drop rhose sessions as close to the year point as you can. But give your self and your child some room to play in terms of weaning. I found that I was very comforted by continuing to nurse a few times a day because of how the breastmilk composition changes after the year point and because my son wasn't keen on cow's milk. By continuing to nurse 3-5 times in a 24hour period of time, I didn't need to sub in other milk fat for brain growth. Which babies NEED. So for me, it took a TON of the pressure off. Allow yourself that. To not feel like is HAS to be DONE by when it's supposed to begin.