I have two gliders here right now. We will be picking up three more this Sunday. They will be kept in separate cages for a minimum of three months due to family plans over the summer and such. I don't want to blend the two groups and leave them with a sitter who isn't super familiar with them. I know before we introduce them, we have to do blanket and pouch switching and such. Is there anything else I can do to get the two groups use to each other over the next few months before we actually introduce them physically? I love the two babies I have dearly and want this transition to go as smooth as possible for them and for our new fur babies we will be welcoming into the family.

So you would be doing the first vet check then the 30 day quarantine starts anyways.
And you might want to think about keeping them in separate rooms if space allows.
I would wait to do scent swapping until the second fecal tests come back negative after the 30 days are up.
You may have a lot of barking and hissing as they will know there are other gliders in the house and will be calling/communicating with each other.
Then after two weeks of the scent swapping and moving the cages next to each other(but 8 inches apart so no-one can grab/pull tails or arms or legs) then you would try indroductions.

With that many gliders to introduce I would read up on that...lol! When I was researching intros there is a few different routes to take on that.

Fecal test? They did not do that on my first set of gliders. Should I request one? I was planning of keeping them completely separate (room) until after June 23rd. Then I was going to get the cages in the same general area (room). After August 18th I was going to start scent swapping. I figure a month of that and then I would set the cages about a foot apart. My biggest thing is that NONE of them get hurt in all of this. If I have to keep two separate cages permanently, that is what will be done. As long as all the babies remain safe.

BTW... the vet visit was a given. Appointment is already made. Even the pair I purchased from my cousin, that she had for about 8 months, went to the vet first thing. :)

It wouldn't be a bad idea for fecals from your first pair to make sure there are no issues...unless they were checked when your cousin had them.

My twins were not fecal tested until I got the new girl either, just had the wellness check to set up info on them with the vet.

Not everyone has followed quarantine advice, so just wanted to throw that out there ;)

The separation and time frame sounds reasonable.

I had my newest girl in a much smaller cage and it was the longest 30 days ever waiting to intro her to my twins. I wanted her out of that little cage A.S.A.P.

As for keeping two cages or combining you are on the right track. I know how much fun it would be for them to enjoy a big colony but sometimes there are gliders that just won't get along. I hope your clan all love each other and get to enjoy a big happy family life!
Keep us posted with your new furkids