Reminders app waking mac from sleep

I've been having 2 issues with my mac staying asleep, this post is about one of them, which is regarding reminders waking from sleep, turning the display on, and not going back to sleep:

iMac (Retina 5K, 27-inch, 2017). Mac OS 10.15. Have two external USB hard drives hooked up at all times.

In Energy Saver, power nap is off, wake for network access is off. In Notifications, Do Not Disturb has the following 3 checked: "When the display is sleeping, when the screen is locked, when mirroring to TVs".

I set up a test reminder, see the `inDelta=137` below.

Abridged log using `pmset -g log` (full log in attached file):

2019-10-12 14:26:25 -0700 Notification        	Display is turned off
2019-10-12 14:26:25 -0700 Assertions          	PID 582(useractivityd) Summary PreventUserIdleSystemSleep "BTLEAdvertisement" 00:00:02  id:0x0x10000a3af [System: PrevIdle DeclUser BGTask IntPrevDisp kDisp]
...
2019-10-12 14:26:25 -0700 Assertions          	PID 119(powerd) Summary InternalPreventDisplaySleep "com.apple.powermanagement.delayDisplayOff" 00:00:58  id:0x0x1000008003 [System: PrevIdle DeclUser BGTask IntPrevDisp kDisp]
2019-10-12 14:26:25 -0700 Assertions          	Kernel Idle sleep preventers: -None-
2019-10-12 14:26:25 -0700 Assertions          	[System: PrevIdle DeclUser BGTask IntPrevDisp kDisp]
2019-10-12 14:26:25 -0700 Assertions          	PID 119(powerd) Created InternalPreventSleep "com.apple.powermanagement.darkwakelinger" 00:00:00  id:0x0xd0000a3b1 [System: PrevIdle DeclUser BGTask SRPrevSleep IntPrevDisp kCPU kDisp]
2019-10-12 14:26:25 -0700 Assertions          	PID 584(sharingd) Released PreventUserIdleSystemSleep "Handoff" 00:02:38  id:0x0x10000a381 [System: PrevIdle DeclUser BGTask SRPrevSleep IntPrevDisp kCPU kDisp]
2019-10-12 14:26:40 -0700 Assertions          	PID 119(powerd) TimedOut InternalPreventSleep "com.apple.powermanagement.darkwakelinger" 00:00:15  id:0x0xd0000a3b1 [System: DeclUser BGTask SRPrevSleep IntPrevDisp kCPU kDisp]
2019-10-12 14:26:40 -0700 Sleep               	Entering Sleep state due to 'Software Sleep pid=205': Using AC (Charge:0%) 150 secs
2019-10-12 14:26:43 -0700 Wake Requests       	[proc=dasd request=Maintenance inDelta=43536] [*proc=powerd request=UserWake inDelta=137 info="com.apple.alarm.user-visible,481"]
...
2019-10-12 14:29:01 -0700 Notification        	Display is turned on