I'm friends with their guitarist Nick. He has a couple side projects as well if you liked Whirr.
He has a side project with Alexandra who used to sing in Whirr. They're name is Camera Shy. Their full length is amazing. Really nice, soft music. Kind of in the vein of Best Coast / Camera Obscura. There is one song on the album that sounds like it could have been an old Whirr b-side because the guitar riffing screams Pipe Dreams.
He is also did these dope Misfits cover songs under the name Orange Hell. Not sure if it's also the girl from Camera Shy but it's basically a Whirr side project as well. I think it's supposed to be a secret that he did that stuff though
When you know that it kind of starts to make sense that the guitar tones and feel of the music are the way they are.
Aside from that, he was also in Deafheaven. Not sure if you're into that kind of music! Sorry for the novel!