I tried it, service doesn't start up after suspend:
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: DEBUG: '_check_hddio(): Actual: kB_read: 1747131, kB_wrtn: 5216189'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: DEBUG: '_check_hddio(): Store new read/write value for device'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: DEBUG: '_check_hddio(): rvalue: 0'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: INFO: '_check_hddio(): All checks complete'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: INFO: '_check_ul_dl_rate(): Running on interface: enp2s0'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: DEBUG: '_check_ul_dl_rate(): Actual: TX kB: 23126092, RX kB: 148838227'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: DEBUG: '_check_ul_dl_rate(): Store TX, RX and epoch values'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: INFO: 'main(): ---------------- Script started ----------------------'
Feb 16 09:57:10 MalibuNAS.fritz.box autoshutdown[328794]: root: INFO: 'main(): Waiting 5 minutes until the first check'
Feb 16 09:57:35 MalibuNAS.fritz.box systemd[1]: Stopping openmediavault-autoshutdown plugin service...
Feb 16 09:57:35 MalibuNAS.fritz.box systemd[1]: autoshutdown.service: Succeeded.
Feb 16 09:57:35 MalibuNAS.fritz.box systemd[1]: Stopped openmediavault-autoshutdown plugin service.