UPDATE (attention BA App team):
- updated my iPhone to App version 5.18.2. Still showing correct Avios and TPs (1,580) under Account details, but scrolling down (to where it would normally show "Progress towards Gold") it says "Gold achieved" but then the dial with "1,579 Tier points" and "No more needed".
- on my iPad (still running App version 5.18.2), Avios and TPs from latest flight are now added and reflected correctly (1,580 Tier points") under "My account", and the same "Gold achieved" message and (bug) 1,579 Tier points dial.
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