
Hello @john john !
If you are concerned about hitting the limit of 50,000 unique items per list in SharePoint online, you may want to consider using a combination of multiple lists and folders within those lists. For example, you could create a new list for each year and then use folders within each list to organize the requests by employee. This would allow you to stay within the limit of 50,000 unique items per list while still keeping all of the requests for a particular employee together in one place.
Another option would be to use a database instead of SharePoint lists to store the leave and vacation requests. This would give you more flexibility in terms of the amount of data you can store and how you can organize and manage it. You could still use Power Apps to build the UI and connect to the database using the appropriate connectors.
I hope this helps!
Kindly mark the answer as Accepted and Upvote in case it helped!
Regards