The problem is that you wouldn't even know what to ask in my case. I just thought that I would have to rank up my level in the island and I unlock the new 6.4 things naturally as you level up.
Usually it even tells you when you have a new tool available to craft. But upon reaching a higher level (14) I started to wonder and I had to ask how I get my new tools, only to get a reply;

"Did you upgrade all the facilities?"

2weeks have gone by and not once has the game even given me a hint I could do that.

I get it if the handholding is withing the storybeats of the game or general quests.

Maybe a fix to this would be the Recommendations window to include Island Sanctuary, so you can open that and see if there's things you could do in there.
Like; Upgrade Facility #1