Weird expression errors in After Effects Beta 17.1.3 (Build 18)

[Alexander from MisterHorse.com]

Steps to reproduce:
    1. Check out my sample project and screen recording here: https://www.dropbox.com/s/w3t4zq8jvua0nlw/Bug%20on%20After%20Effects%20Beta%2017.1.3%20%28Build%2018...

Result: 

• When I open the sample project in latest Beta I see an expression error
• Sometimes turning on and off a layer or moving playhead fixes the error
• When changing the controls on "Controller" layer all sorts of weird errors happen which were not happening in previous versions

Expected:

• No expression error
• These expression errors were not happening on previous versions of After Effects 2018-2020 
• The expression errors do not make sense - for examle "Couldn't turn into numeric value" when dividing a number property by 2.

 
System info
    Application: After Effects (Beta) v17.1.3.18
    OS: macOS v10.15.5, RAM: 32.00 GB, CPUs (logical): 12

Let me know if there is anything more I can provide. 

Cheers

[JohnColombo]

Hi Alexander,

Thank you for reporting this issue. The development team is aware of this breakage and is looking at possible solutions. It is currently being tracked internally as DVAAE-4215701. We'll keep this thread updated as a fix becomes available.

Thanks again Alexander! Your feedback and reporting is very much appreciated.

- John, After Effects Engineering

[Alexander from MisterHorse.com]

Perfect, thanks for looking into it. It seems to be somehow manifesting in Premiere too (mogrts not working as expected), I've reported it on the Premiere Beta forum too. 

The issue is still happening in 17.1.3x19. Feel free to reach out anytime, if there is anything I can help with.

Cheers