Due to the current v9 on-premise 32bit architecture restriction Tealeaf Hit Attributes and Event buffers are limited to 256 characters.
In certain scenarios, such as looping through multiple values within a page and concatenating results "abc,123,xyz" this char limit can be easily reached. At this time values are truncated, which is the expected and documented outcome.
Within Tealeaf 10 (on-premise) we have multiple use cases where increasing the char limit has significant business benefits. One customer requirement we have meets this and they have requested an enhancement request.