I found this on cruising forum website.
Amel Super Maramu #376 Kimberlite
Despite doubts over the case, Spade have agreed to modify future bolts, as
recommended by the investigator, to include a pin after the nut and a note
advising that "Nyloc" style nuts should only be used once. (There is no need
to replace the nut after each deployment, but every time the anchor is
dismantled). Existing owners are advised that if they have any concerns
about their nuts, that they arrange for the end of the bolt to be drilled
and have a pin and new "Nyloc" style nut fitted. It is the owners'
responsibility to ensure that the nut & bolt (or alternative) are in good
condition, secure and suitable for the purpose. It must be emphasized that
thousands of Spade Anchors have been sold since 9 years, and that no similar
cases have been reported.