Most likely cause
A pre-release discussion places the XP readout on the portal screen and the actual level-up interaction at the Goddess Statue, with mana stones used during prayer.
Primary lead: Steam level-up / XP discussion
Quick fix · Expedition route order
Symptom: A settler has finished expeditions but no level-up button appears on the normal character panel.

Legacy test path—reconfirm every label and control in the EA build.
The settler’s level changes and the chosen buff or stat result appears. Seeing a full XP bar alone is not completion.
Why this answer is still partial
The discussion lead describes the portal-screen XP bar, Goddess Statue, prayer, and mana stones.
An independent thread confirms mana stones are frequently consumed for leveling.
