Sorry, forgot the reference for [1] previously:

https://bbs.archlinux.org/viewtopic.php?id=222401

I can also confirm that adding the line "disable-ccid" to scdaemon.conf appears
to revert to the previous system, which then works fine (but doesn't really fix
the issue).

Having read [1], I double checked my scdaemon.conf (which apparently already
featured debug-all) and made sure it to read as follows:

log-file /home/mike/.gnupg/scdaemon.log
debug-all

I got the following from attempting to run gpg --card-status:

2017-02-02 18:00:58 scdaemon[32091] DBG: chan_5 <- GETINFO version
2017-02-02 18:00:58 scdaemon[32091] DBG: chan_5 -> D 2.1.18
2017-02-02 18:00:58 scdaemon[32091] DBG: chan_5 -> OK
2017-02-02 18:00:58 scdaemon[32091] DBG: chan_5 <- SERIALNO openpgp
2017-02-02 18:00:58 scdaemon[32091] DBG: apdu_open_reader: BAI=10a02
2017-02-02 18:00:58 scdaemon[32091] DBG: apdu_open_reader: new device=10a02
2017-02-02 18:00:58 scdaemon[32091] ccid open error: skip
2017-02-02 18:00:58 scdaemon[32091] DBG: chan_5 -> ERR 100696144 No such device
<SCD>
2017-02-02 18:00:58 scdaemon[32091] DBG: chan_5 <- RESTART
2017-02-02 18:00:58 scdaemon[32091] DBG: chan_5 -> OK

Please let me know what further information I can provide to help debug this?