Premiere .prproj file ticks drift by 1/1000 compared to timecodes
First, let me say that I have no idea what Premiere is doing with its values or what a 'tick' means in their terms. I can only speak generally.

The video frame rate should match the timecode rate, but for 'drop frame' timecodes the relationship isn't perfectly linear. There are certain timecode numbers that never show up in the sequence -- the ones that are 'dropped'. So for such codes you can't just perform a simple computation, you have to consider the drops.

Over the course of 1 hour there are 108000 frames at 30fps, but drop frame code will produce only 107892 unique numbers. Both clocks will agree that "the time" is 1:00:00:00.

If you're just using timecodes to label each frame with a unique number then any scheme will do. If you need to match time of day, then you have to take the dropped numbers into account. What do you need to do with your values?