Expression Map - Keyswitch Before / After Note

Hello… in an expression map, is it possible to define if a keyswitch plays before vs. during the playing of a note… from the VST manual:

" G0 ‘Slide note’ keyswitch: If activated before a note, performs a slide from the end of the fretboard up to that note. If activated during a note, performs a slide from that note down to the end of the fretboard.

It’s not possible at the moment, no, though it has been requested before and is something we may well add in a future version.