How to allocate resources within a group

Hi folks,

I have a many months-long project being worked on by a 4-person team. There are hundreds of tasks in this project. I have all the predecessor and successor relationships built and I'm working on assigning resources. My issue is that some of the tasks need to be worked by specific team members, but some of them can be worked by any of the four. I also know that one team member is taking a month-long vacation in the middle of the project and I need to account for that.

I previously had created a version where I just created a resource named "Team" and set the max resources to 400%. I can account for the month of vacation easily this way, but this doesn't allow me to assign a specific task to a specific person. Tasks that need to be worked by team member A are thus being scheduled while they are on vacation.

I thought about creating individual team member resources in addition to the overall team resource, but that would mean the maximum allocation for the general team resource would fluctuate with time based on how many people are working their own, specific tasks. In other words: I find myself in the situation where team members a, b, c, and d are all working on their own tasks, but then the "Team" resource is also working 4 other tasks at the same time because the "Team" resource doesn't know that a, b, c, and d are already busy...

Any thoughts on how I might accomplish what I'm looking to do? Maybe there is a global setting that I could set saying "no more than 4 tasks at a time"? Or is there a way for project to handle individuals as part of a group?

Using Project 2019 Professional

Thanks in advance for any help!