Hi, .28 version are not working anymore with Yubikey 4 NEO, this happen in .24 and in .25 we got a few problems (T5167) with was corrected on .26
I have uploaded the log from scdaemon from 2.2.27 and 2.2.28 as was instructed on T5167 issue.
log-file /somewhere/scd.log verbose debug ipc,reader,app debug-ccid-driver
The the only command I have used while running each version was gpg2 --card-status