I also doubt it’s related, seeing as this is a completely deliberate “Feature” Funcom implemented 
Basically whenever you try to use anything from BP / Bazaar, an online query is made via Funcom Live Services to see if your account is “entitled” to use the item in question… if not, you get the message.
Pretty much overly-protective DRM… nothing more…
I did mention in a post in the past that I also think they should revise this decision. While the usefulness is understandable as this will prevent people from skipping updates and to some degree also further combat piracy, however the nature of it is just too aggressive imo. and it reaches a point where it’s disruptive to the game itself.
For example imagine you have a wight horse from the previous BP, you travel somewhere far in SINGLE PLAYER… and then a temporary internet outage won’t let you mount your horse and ride back… that goes beyond what is an acceptable DRM measure imo. and as I pointed out in the past… we’re talking about cosmetic items… and not nuclear launch codes… so maybe a bit of a reality-check is in order… just saying
At the very least they could change it so the list of “entitled” items gets validated once at startup and then stored in memory for the session at least minimizing the above disruptive nature of it. It still won’t solve the issue of the topic, but it’s better than nothing.