This script uses the Heroku Platform API to scale your Dyno formation up or down. All you need to do is to schedule jobs using the Heroku Scheduler (free!) and set up some env variables. Really handy to keep costs to a minimum (e.g. turn off my dyno at 8 pm and back on again at 7 am next day).
MY_HEROKU_API_TOKEN=****
APP_NAME=my-app-name
DYNO_TYPE=web
WEB_HIGH=1 // maximum number of processes
WEB_LOW=0 // minimum number of processes
SCALE_DOWN_AT=19 // the hour to scale down your dyno formation in your timezone
TZ='Australia/Sydney'
https://devcenter.heroku.com/articles/scheduler
Enjoy!