Underfloor Water heating - Night lowering

[Bobby]

Hi!

I am using PID script for UFH. And i want to have 2 adjustable setpoint temperatures for day/nighttime.
is this possible? 
Another alternative is to use the current setpoint temperature, but lower it by ie 4 degrees in night time.
My current script:

-- init pid algorithm
if not p1 then
  p1 = PID:init({
    current = '1/5/41',
    setpoint = '1/5/21',
    output = '1/5/1'
  })
end