Threshold calculations inconsistecies

Yesterday , after my workout, the system calculated my TP at 199 watts. A couple of hours later it lowered it to 198. Did the system make a mistake in the calculation? I did, EXACTLY the prescribed workout! Either I have it or not. Then , my anticipated goal of 218! ( calculated by xert) for April 1st, was lowered from 218 to 217. It appears trivial, however if it calculated to be 199, it should at least latch that value until after the next workout. As a comparisson , if my VO2 max for running is 55, if I do a slow run, it does not get lowered to, say, 50! My fitmess is still,the same…Likewise, if I a have a LT of 199, an hour later my fitness does not decrease to 198. My concern is that if I have doubts in the short term calculation ( lowered within a couple of hours) how can I trust that by April 1 ( following xata recommendations ) I,ll get to what xert kept stating.

I would say don’t freak out about 1 watt, or 0.5% difference. Your real threshold for the day may vary more than that depending on what you had for breakfast. And also realize that most powermeters have a +/- 2% accuracy range. Its all good…

Actually, its none of that and I figured it out. The calculation that xert makes is incorrect. The required xss should be directly proportional to real time and as (Max ( xss) required for the day)/ time + Xss debit/surplus. its all good," Even if they dont fix it, I, now ,do not get surprised because I know e axactly what the numbers are.