I see this error as well - that is why I'm on this thread, reading through it ....
I'm trying to reconcile this thread with Coinbase's recent email. Are we talking about here the User Activated Soft Fork (UASF) that Coinbase is referring to?
Coinbase also refers to User Activated Hard Fork (UAHF) that is scheduled for Aug, 1st. They are not supporting this fork.
This error is related to the UASF - which does not require a software upgrade on wallets of core 14+ (or some 13s versions), and Coinbase is supporting?
Is this coinbase message since we started seeing the BIP 91 signaling? What is coinbase saying in their message? Some of us on the thread aren't coinbase customers.