It would be cool if it were possible to use expressions, and bound variables in particular, in time intervals for temporal operators. Something like this:

rule "Sound the alarm with parametric delay"
when
$f : FireDetected( )
not( SprinklerActivated( this after[expr: $f.start, $f.end] $f ) )
then
// sound the alarm
end

A similar request was made for the interval-based timer in this issue:
https://issues.jboss.org/browse/JBRULES-3402