Hello and welcome, Learner,
You just need to make sure nothing pulls this line low right at power up. If you are using this pin for an output, you don't really need a timer as the code will not change the mode into output until the device is already in run mode.
So if you are going to put some circuitry on this pin, like a simple base resistor and NPN transistor this will probably cause (or possibly cause) entry into background mode. In this case you will need some additional circuitry in between like a buffer gate or a PNP transistor that then drives the NPN.
You don't need to actively drive this pin high, just don't bias it low!