asterisk users - Jan 2015 - weird stasis_cache.c error in Asterisk 13.0/13.1 version

Hi all

We have recently upgraded Asterisk from 1.8.26 to 13.0.0 and now we have 
a whole lot of errors like this in our logs:

[2015-01-05 06:43:36] ERROR[14636] stasis_cache.c: Attempting to remove 
an item from the SIP/ics0002-cached cache that isn't there: 
ast_endpoint_snapshot_type SIP/ics0002

Any ideas what it might be related to ? And how could we fix it ?

Upgrade to 13.1.0 did not improve a lot here, such errors continue to 
appear in logs.

Should I create an issue on Asterisk bug tracker ?

Many thanks for your support

Kirill M