Hi Alex,
I am looking into this right now, reached out to check in on it as I am also seeing a 50 limit in the Kanban reports I build in my own apps. I'll let you know when I hear back with something more definitive or you can also submit a case with our Care team to have them look into it with you as well. You can reach out to our Care team by clicking on the Support option that appears in the community in the upper right hand corner or when in Quick Base by selecting the question mark (?) icon that appears in the upper right hand corner and selecting "Manage Support Cases" that would get you in touch with a Care rep who would work with you directly if you wanted to go that route while I wait to hear back.
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Evan Martinez
Community Marketing Manager
Quick Base
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