Hello zeroality and welcome to the forum.
You can also go to the GUI > Settings > Updates > and change the Engine and Virus Definition Update to "Ask When Update is Available." In the meantime, you can still force a Manual Update yourself. You just need to remember to do this to keep yourself up to date.
Your other option is to change the time interval for getting your updates as mentioned in the post by Pondus.
To answer your question: Avast usually does 2 updates a day, but on a rare occasion will release a third. So you should be fine doing 2 updates a day. Please let us know if we can provide any other assistance to you. Thank you.