EventsJSON
EventsJSON pages through concerts, newest first (limit <= 50): offset and limit count stored concerts, hidden ones are left out of the page, and "next" gives the offset of the following page (0 at the end). upcoming=true lists future, not cancelled, visible concerts instead, soonest first, with offset and limit counting listed concerts ("next" is then a listed-concert offset, 0 when the scan ended).
Command
gnokey query vm/qeval -remote "https://rpc.onyx.testnets.gno.land" -data "gno.land/r/nym-alexiscolin000/gnoradio/tickets/v1.EventsJSON(,,)"
Result