How long should I wait for the next maintenance after adding semi-synthetic oil?

What engine oil is recommended for the Jinxuan 4B11? I've been using the original 5W30 mineral oil from the 4S shop for over 5 years (people say it's like gutter oil [lol]). I want to switch directly to fully synthetic oil. Any recommendations? Some say you should transition with semi-synthetic oil before switching from mineral to fully synthetic. Is this necessary for the Jinxuan?

Yesterday, I went for a car maintenance, and the oil draining took a bit longer. The mechanic said that adding just over 4 liters of oil wasn't enough, so they added a bit more, totaling 5 liters. Is this reasonable?

Hey folks, got a low oil warning and the next day it started making noise. Even after adding 4 liters of oil, it's still the same. Any idea why?

Second maintenance hasn't reached 5000 km yet. Should I use the complimentary oil or switch to synthetic, guys?

Do you use fully synthetic oil or semi-synthetic oil for your 308?

What should I pay attention to for the second maintenance of the VS7? Any tips from experienced drivers? Do I need to use fully synthetic oil? Currently, it has run 9,200 kilometers.

Do you use fully synthetic or semi-synthetic oil for your 10,000 km oil change?

Changan CS35 Plus, 2023 model, uses CTS-03.08.06. 0W-20 Changan-specific full synthetic oil. How many kilometers should it be driven before an oil change during maintenance?

How long should I wait for the next maintenance after adding semi-synthetic oil?

For the 2023 Changan CS35 Plus, when using the CTS-03.08.06.0W-20 Changan-specific full synthetic oil, how many kilometers should the oil be changed during maintenance?