Live upgrades and boarding zones

Flow tickets are dynamic — a guest isn't locked into what they bought.

Live upgrades:
When a scan denies someone for "no access" (say a GA pass at the VIP Lounge), the scanner shows a "Sell an upgrade" panel right on the verdict screen. Enter an amount and tap Charge & admit, or Comp it — the new access works on the very next scan. You can also add access from the Credentials tab ("Add access"). An upgrade to a point that is currently full fails gracefully rather than handing out a pass that would just be denied. Paid upgrades post to Accounting automatically.

Boarding zones:
The Boarding tab sequences guests into zones. Order your priority buckets (higher-service tiers first), then hit "Resolve boarding zones." The resolver keeps travel groups together and — when seat data is present — orders back-to-front and window→middle→aisle. The /flow/board projector view shows live occupancy and the boarding order on a big screen.