You can load TH/TL2 the first time to get the first pulse at a precise time. I have, however, found that in all cases I have seen it did not matter, the time before the first T2 overflow is coming after a reset and some code that get executed before T2 is started, thus it will never be precise anyhow. After the first overflow the auto-reload will happen regardless of the original TH/TL contents.

Have fun,

Erik