When creating an AWS Batch CE using Seqera Platform, there is an option to set both the EBS blocksize and also the boot disk size:

The CLI offers an argument to set the ebs blocksize, but there is no argument for boot disk size:
--ebs-blocksize=<ebsBlockSize> This field controls the initial size of the EBS auto-expandable volume. New blocks of the same size are added
as necessary when the volume is running out of free space [default: 50 GB].