Im on season 6 of MyTeam and cannot upgrade my car and havent been able too for a couple of seasons (Season 4), same with the facilities. Now all other teams are developing in front to the original order and i can do nothing about it and it puts my team to the back of the grid.
The new regulations each season doesnt work as the parts get re developed within a couple of races and the same for most of the AI teams as there is a massive influx in cash and R&D points not being used. Meaning the original order is back to normal a couple races into the season. This basically means MyTeam is unplayable around season 5/6 onwards as you cannot upgrade your car.
I Saw a post on Reddit and in your patch notes of the community manager stating the issue was fixed in 1.07, but has rather delayed it from happening in season 2/3 to now season 4/5. A solution is to remove the research parts as well as the developed parts to fully reset the grid in the new regulations. As well the facilities or cash you recieve needs to be massively changed so you dont get max facilities within 3 seasons. It should be atleast season 5/6 where you get phase 4. With some upgrades still left for the last few seasons. I understand most people dont play all seasons, but why have 10 seasons if you cannot play past 5, you can play 10 seasons of driver career fine.