After a club is edited the club field values remain at the state so the changes are visible. If the page is reloaded the server side rendered page is served and the old values appear again until the page rebuild is finished.
After a member is added to the club through the "Become a member of this club" CTA it does not appear in the member listing at the bottom of the club page so there is no indication of the success of the action.
Possible Solution: After the mutation is finished we should re fetch the club data and populate the page.