Add/remove photos in a pinned FB post without affecting likes and comments

READ CAREFULLY BEFORE BIDDING - I ONLY NEED HELP WITH THIS

I want to run a weekly FB giveaway without losing the likes and comments of the previous giveaway. People share and comment on a photo, and then after the winner is announced and the second giveaway starts, I change the photo to a new giveaway but the likes and comments stay the same. (So that the page looks like it has a lot of engagement and orders. )

I run an online store on Facebook, and I would like to copy the work of another fan page, that has a viral massive following without much quality in photos or marketing.:

[url removed, login to view]

I see they only upload photos from mobile phones, to their Mobile Uploads default album. I clicked on their "see edit history" tab of this pinned post ([url removed, login to view]) to see what they did to the post and saw this: [url removed, login to view]

So, my questions are these:

1.

I want to know how to upload photos to our Mobile Uploads album, pin it, and then edit the text AND the photos. Afterwards I want to be able to upload other photos to the same album without it affecting the pinned post, the likes and comments should stay intact, and the pinned post should also have the same photos, and not the photos uploaded afterwards. (I tried pinning the album, but it didn't work)

2.

I want to run a weekly FB giveaway without losing the likes and comments of the previous giveaway. People share and comment on a photo, and then after the winner is announced and the second giveaway starts, I change the photo to a new giveaway but the likes and comments stay the same. (So that the page looks like it has a lot of engagement and orders. )

This is a pretty viral marketing around the countries where we live, and I want to know how exactly do they do it. My main focus is how to accumulate all the likes and comments on one place, so that people who visit out fan page see others are interacting, ordering from our shop, commenting and liking.

Thanks

Marketing de Facebook

ID do Projeto: #12505497

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