formula [ variable - delay(variable, dt, 0) ] not working

[tedchwang]

Describe the bug
A formula of the form variable - delay(variable, dt, 0) generates an error of node not found.

To Reproduce
Steps to reproduce the behavior:

1. create a formula of the form variable - delay(variable, dt, 0) where "variable" is an influencer of the node.
2. Click on 'calculate baseline'
3. See error

Expected behavior
I expect the formula to calculate correctly.

Screenshots
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Desktop (please complete the following information):

• OS: Windows 10
• Browser: chrome
• Version of mipa web app: [if different from production version at mipa.collective-change.org]

Additional context
Add any other context about the problem here.

[tedchwang]

Unable to reproduce.

[tedchwang]

Able to reproduce bug when the variable is an intermediate node.