When making lemon/poppy seed icecream, how should I include the poppy seeds?

(quick googling)

This lemon/poppy seed recipe adds the seed to the chilled mixture before churning the ice-cream.

Other recipes seems to have more or less the same steps, add the seeds to the chilled mixture.

I would assume adding seeds would be a lot like adding other things such as cookies, candy, nuts, chocolate, etc. In those cases, I've found that it works better to add them at the end, since they can sometimes be large enough to interfere with the machine's dasher. And for softer things like cookies or brownies, or swirls of things like caramel or jam, you pretty much have to add them at the end to avoid them either disintegrating or just getting lost in the ice cream.

Some recipes say to add extras to the ice cream in the last couple of minutes of freezing in the machine, but I've found that it's better to pre-chill a ceramic bowl and then transfer all the ice cream to the bowl using a pre-chilled spoon before folding in the extras. You don't have to worry about getting the timing just right and it works better for machines where the top is covered and all you have is a small chute.

In the case of poppy seeds, you may find that they're small enough that you can add them at the beginning without interfering with anything but in general I think adding things at the end works better for me. That's the way it's done for commercial ice cream as well, where the extras are dropped into the stream of frozen ice cream as it leaves the machine.