You can implement a call queue, so just wait until 5 calls have finished before sending the next 5. In short, setting up a call queue let you bypass the call limit is quite straightforward. However, Scripts have limited memory resources and creating a large object with numerous calls can consume a significant amount of memory forcing the script to stopp automaticly, but 10-30 calls should not be a problem.
Needed to test it a bit to fully understand that you need to give different time intervals for each timer, as script won't stack them on top of others. Instead it executes the setting of timer at first (if set one after other in the script) and then executes the timer script based after timer value has exceeded (like a delay).
Thanks for advice, seems to work!