Sync Token Expiration on /events

This is just a general question, but I am reading in the docs about the sync token used with the /events endpoint, and there is not a concrete answer as to how long the token lasts.

From the docs:
Sync tokens always expire after 24 hours, but may expire sooner, depending on load on the service.

I have also read other posts such as the following that seemingly detail an undetermined amount of time a token is active. From Matt_Bramlage on Events api and sync tokens

Our events are intended to be used for something close to real-time updates, and using them once per day is stretching things a bit; they do expire after a short while. They are also only a best-effort resource for real-time sync and sometimes (particularly if Asana is having an issue) they can end up getting lost

Could anyone give me more details into when these actually expire, or how long I can expect a token to stay active? Are there any more official timing details that can be shared for this?

Also, what kind of things (Asana issues, etc.) might cause a sync token to “end up getting lost”?