Previous software versions state when using the frame calculator - to match Uplink Rcv SQ Start as closely as possible (within 150 time slots if possible). The GUI for 10.3 and later don’t show the value as Uplink Rcv SQ Start but instead have two bold numbers: AP Transmit End and AP Receive Start.
Which value equates to Uplink Rcv SQ Start in 11.2 firmware?
Try looking at the two documents here : viewtopic.php?f=36&t=6884&hilit=frame+calculator
They show the changes that happened right around the 10.2 software release.