It is the maximum number of customers or suppliers with whom you can have transactions with (sales and/or purchases) within a 30-day period. The number of transactions you may have with these customers / suppliers is unlimited. For example, if you have issued 5 documents to customer A and you have made 3 purchases from supplier B, the total number of customers / suppliers you use in your plan is 2.
In Elorus, only sales and purchase documents are considered as transactions with customers / suppliers. This means that you have the ability to create unlimited entries of revenue or expenses, regardless of subscription plan.
The "per month" restriction refers to a period of 30 days, starting from the current date / time and going back. For example, if you issue a new document to a customer on April 3rd, this transaction will occupy one client slot until May 2.
Note that the application records the date / time you actually created the transaction at Elorus and does not take into account the issue date or any other date.