I think the issue is that the Gallery itself, is only pulling in 2,000 rows and therefor you do not believe your filter, which has only 700 out of the 4700 are being returned correctly, because you think that the Gallery is only allowing you to Filtering on its 2,000 rows, versus the BackEnd that has 4,700
Is that correct? Which means, you think you are only going to get... for example 400 of the 700?
So you want to make sure that the Filter you do, based on the Choice is going against all 4700, not the 2,000 you think the Gallery has?
Is that accurate?
Unless you are specifically running a filter on the gallery.allitems and allitems only has 2,000 (which should not be the case), then you should filter against the back end not the Allitems in the Gallery
So I do not understand why there is a need to create multiple Collections etc.
What I would ask really to you is, do you need your Gallery to pull in all 4700, or do you just need it to connect show the first 2,000 and then have people filter down to where it will NOT be over 2000 and it will be delegatable?
Situational Awareness of need is important in these decisions.
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