Can’t find any news about an unlock. Please provide as much info as you can, including info about Shard to Get, Silver Lining, etc. I just got a StG and I’m wondering if it’s worth holding onto for the squiggy chance.
As Scoria said, it's more related to patches than to scheduled in-game events, as relic odds are sort of hard-wired into the system and it takes a formal update to change them. We're not sure yet on when 2.4 will be landing, but along with Squigly's assumed full release there will be a large chunk of new content as well, so look forward to that too!