In 6WE there are no established training times. The rule is training takes whatever period of time the GM wants it to take. The charts given in the CRB are literally only a suggestion. I'll grant that I also think they're a terrible suggestion, but the fact remains they're only a suggestion. Training time can instead be measured in days or even hours, if the GM sees fit.
...I'm sure Missions will set some sort of base time frame to keep things form getting out of hand since time is so "fluid" between sessions.
In 5E the base time was pretty well set down. 1 day x new rating up to rating 4, 1 week x rating for rating 5 - 8, and two weeks x new rating for nine or above. Skill groups took two weeks x new rating and specializations one month. pretty straightforward, no GM input or decision needed.