go1.10.6 (released 2018-12-12) includes three security fixes to "go get" and the crypto/x509 package. It contains the same fixes as Go 1.11.3 and was released at the same time. See the Go 1.10.6 milestone on our issue tracker for details.
Thanks for highlighting the bet limit and expiry dates; those are the details I usually miss when reading a welcome offer.