Repeating Tasks failing to sync properly

[NginUS]

I'm on Linux Mint 18.3, Thunderbird 60.2.1, Lightning 6.2.2.1, Android Nougat, & DAVDroid 2.0.5

As you can see in the below referenced screenshots, tasks- specifically repeating ones, are failing to update on desktop [0] when marked complete on mobile [1].

I sync between Android & FastMail using DAVDroid, then from FastMail to Thunderbird/Lighting via the associated DAV account.

Earlier this week when I was testing after first setting it up, it seemed to work fine. If I had to guess as to what might have changed to make it fail today, there was one thing I noticed during my initial tinkering was that it would get wonky while updating overdue repeating tasks. Much like what I'm seeing today. Eventually that stopped happening, & as long as I would check one done at a time it was fine. Last night I marked numerous repeating tasks complete while they were overdue, & on mobile they appeared to be advancing fine. Later when I looked at the desktop it was all screwed up again.

[0]
https://files.catbox.moe/40qa7i.png

[1]
https://files.catbox.moe/vx81ar.png

[NginUS]

Received a reply from the developer, stating:

This should be fixed with the upcoming 2.0 release.

Will check back afterward with status.

[NginUS]

Version 2 was released yesterday & now recurring tasks marked complete on Android indeed sync properly to Desktop. However there are severe problems remaining.

Only recurring tasks created on Desktop will increment to their next due date properly after being marked complete. The recurring tasks created on Desktop can be marked complete either on Desktop or Android & be expected to increment properly.

Recurring tasks created on Android fail to increment properly when marked complete on either Android or Desktop. They'll look like they've incremented to their next due date on Android, but on Desktop their 'Due Date' field remains set to the date the task was created rather than the next due date, & as such will show as overdue. The 'Start' date is what is visible as having been incremented when looking at the task on Desktop. The Android version calls this 'Start' field 'Due', & doesn't differentiate between 'Due' & 'Start' date/times.

I've emailed the developer with MB's of screenshots in hopes of finding a solution. Will post updates here.

[WaltS48]

Received a reply from the developer, stating:

This should be fixed with the upcoming 2.0 release.

Will check back afterward with status.

Developer of what exactly?

[NginUS]

Developer of what exactly?

Wow, I certainly failed to mention that- sorry. aCalendar, & the add-on aCalendar Tasks- by Tapir apps.

I should mention it's started to behave better now during normal usage than it was when I was testing it by purposefully making stuff happen. Was going to wait until later tonight to see if it continued, but for now it's looking good. Better than it was when I wrote this.

[NginUS]

it's started to behave better now during normal usage than it was when I was testing it by purposefully making stuff happen. Was going to wait until later tonight to see if it continued, but for now it's looking good.

I wish this were the case consistently. However, it's not. Incredibly frustrated with this not working no matter what I do. Tapir Apps don't work weekends apparently. Who knows how long it'll take to hear back from them. Has been a month dealing with this now.