fly deploy --remote-only timing out

Hoping to push changes to our previously deployed fly image, but it refuses to upload on my M1 mac. It used to work, but I am unsure what has changed since then. It uploads normally on my x86_64 linux box.
Terminal output below:

benwis@M1Macfolder % fly deploy --remote-only                         
==> Verifying app config
--> Verified app config
==> Building image
Remote builder fly-builder-delicate-dew-4506 ready
==> Creating build context
--> Creating build context done
==> Building image with Docker
--> docker host: 20.10.12 linux x86_64
[+] Building 354.3s (0/1)                                                                                                                   
 => [internal] load remote build context          

Anyone have any tips or advice? I tried deleting and reinstalling the fly CLI, but that didn’t change anything.